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Exhibit 10.56

CONFIDENTIAL COMMUNICATION PURSUANT TO THE MANAGEMENT AGREEMENT SECTION 14.1.5,
RULE 408 OF THE FEDERAL RULES OF EVIDENCE AND ALL OTHER APPLICABLE PROTECTIONS

LIMITED WAIVER AND CONSENT AGREEMENT

        This Limited Waiver and Consent Agreement, dated March 3, 2008 (the
"Agreement"), is made and entered into by and between Sprint Nextel Corporation
(formerly known as "Sprint Corporation"), Sprint Spectrum L.P., WirelessCo L.P.,
Sprint Communications Company L.P., Sprint Telephony PCS, L.P., and Sprint PCS
License, L.L.C. (collectively, "Sprint"); iPCS Wireless, Inc. ("iPCS Wireless"),
Horizon Personal Communications, Inc. ("Horizon"), Bright Personal
Communications Services, L.L.C. ("Bright") and iPCS, Inc. (collectively with
iPCS Wireless, Horizon and Bright, "iPCS).

RECITALS

        A.    iPCS Wireless and certain of the Sprint entities referenced above
are parties to a Sprint PCS Management Agreement, dated as of January 22, 1999,
as amended (the "iPCS Wireless Management Agreement"). Horizon and certain of
the Sprint entities referenced above are parties to a Sprint PCS Management
Agreement, dated as of June 8, 1998, as amended (the "Horizon Management
Agreement"). Bright and certain of the Sprint entities referenced above are
parties to a Sprint PCS Management Agreement, dated as of October 13, 1999, as
amended (the "Bright Management Agreement" and together with the iPCS Wireless
Management Agreement and the Horizon Management Agreement, the "Management
Agreements"). iPCS Wireless, Horizon and Bright are direct or indirect wholly
owned subsidiaries of iPCS, Inc.

        B.    Sprint and iPCS entered into the Sprint/iPCS Forbearance
Agreement, dated July 28, 2005, which agreement was amended by Amendment No. 1
to Sprint/iPCS Forbearance Agreement, dated as of December 12, 2005 (as amended,
the "Forbearance Agreement").

        C.    Sprint is prohibited by the Forbearance Agreement from taking
certain actions in the Service Area.

        D.    Sprint's continued compliance with the Forbearance Agreement and
with the final order and judgment of the Delaware Court (as defined below) are
conditions to the Stay of Judgment Pending Appeal ordered by the Appellate Court
of Illinois on October 13, 2006.

        E.    Sprint and iPCS have reached agreement as to certain matters,
which agreements are set forth in Addendum X to Sprint PCS Management Agreement
and Sprint PCS Services Agreement, dated March 3, 2008, among Sprint
Spectrum L.P., SprintCom, Inc., WirelessCo, L.P., Sprint Communications Company
L.P and iPCS Wireless, Inc.; Addendum IX to Sprint PCS Management Agreement and
Sprint PCS Services Agreement, dated March 3, 2008, among Sprint Spectrum L.P.,
SprintCom, Inc., WirelessCo, L.P., PhillieCo, L.P., APC PCS, LLC, Sprint
Communications Company L.P. and Horizon Personal Communications, Inc.; and
Addendum V to Sprint PCS Management Agreement and Services Agreement, dated
March 3, 2008, among Sprint Spectrum L.P., SprintCom, Inc., WirelessCo, L.P.,
Sprint Communications Company L.P. and Bright Personal Communications
Services, LLC (collectively, the "Amendments").

        F.     In consideration for the Amendments, iPCS desires to waive
compliance by Sprint with certain provisions of the Forbearance Agreement as
described herein.

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AGREEMENT

        In consideration of the recitals and mutual covenants and agreements
contained in this Agreement, the sufficiency of which consideration is hereby
acknowledged, the parties, intending to be bound, agree as follows:

ARTICLE I

DEFINITIONS

        1.1    Certain Definitions.    The following terms are used in this
Agreement with the meanings assigned below:

"CDMA Customer" means subscribers of products and services offered by Sprint PCS
and Sprint PCS Affiliates using the CDMA Network who are assigned to the Service
Area.

"Ongoing Litigation" means the following litigation: (i) in the Circuit Court of
Cook County, Illinois, entitled iPCS Wireless, Inc. v. Sprint Corporation,
WirelessCo L.P., Sprint Spectrum L.P., SprintCom, Inc. and Sprint Communications
Company, L.P. (Case No. 05 CH 11792), which is currently on appeal in the
Illinois Appellate Court for the First District and (ii) in the Court of
Chancery of the State of Delaware (the "Delaware Court") entitled Horizon
Personal Communications, Inc. and Bright Personal Communications Services, LLC
v. Sprint Corporation, Wirelessco L.P., Sprint Spectrum L.P., SprintCom, Inc.,
Sprint Communications Company L.P., Nextel Communications, Inc., Phillieco L.P.
and APC PCS LLC (C.A. No. 1518-N).

        "Sprint" means Sprint Nextel Corporation and its Subsidiaries.

        1.2    Other Capitalized Terms.    Capitalized terms used but not
defined herein shall have the meanings assigned to them in the Forbearance
Agreement and the Management Agreements.

ARTICLE II

WAIVERS

        2.1    Ensemble Billing Platform.    From and after the date that iPCS's
migration to the Ensemble billing platform has been completed, and
notwithstanding anything to the contrary in the Forbearance Agreement:

        (a)   iPCS acknowledges that, solely as a result of the migration of
iPCS to the Ensemble billing platform, customer information relating to CDMA
Customers will be accessible by Sprint employees involved with iDEN Products and
Services. Accordingly, iPCS hereby grants Sprint a limited waiver from Sprint's
obligations in Section 2.1(b) of the Forbearance Agreement, insofar as such
section obligates Sprint to prevent billing systems containing data relating to
CDMA Customers from becoming available to employees of Sprint that are involved
with iDEN Products and Services in the Service Area; provided, however, that
(i) the foregoing waiver shall apply only to the extent that such data relating
to CDMA Customers becomes available to Sprint employees as a result of it being
accessible to such employees on the Ensemble billing platform and (ii) Sprint
shall use its best efforts to ensure that such data relating to CDMA Customers
is not used by Sprint employees involved with iDEN Products and Services to the
detriment of iPCS's business. Notwithstanding the foregoing waiver, Sprint
employees having access to such data shall remain bound not to utilize such data
for purposes which are otherwise prohibited by the Forbearance Agreement or the
final order of the Delaware Chancery Court.

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        (b)   iPCS acknowledges that the Ensemble billing platform is a unified
billing platform that does not differentiate between CDMA and iDEN accounts and
would permit a customer to have both technologies on a single account. As a
result, iPCS acknowledges that Sprint will no longer be required to maintain a
process of identifying and directing to designated customer service
representatives CDMA Customers who contact Sprint for customer care services and
iDEN Customers who contact Sprint for customer care service. Accordingly, iPCS
hereby grants Sprint a limited waiver from Sprint's obligations in
Section 2.1(c)(i) of the Forbearance Agreement to maintain such a process.

        (c)   iPCS acknowledges that Sprint's Ensemble billing platform does not
treat a customer network change as an event that would trigger a termination
fee. As a result, iPCS acknowledges that Sprint will no longer be required to
charge termination fees when a CDMA Customer transfers from CDMA Products and
Services to iDEN Products and Services. Accordingly, iPCS hereby grants Sprint a
limited waiver from Sprint's obligations in Section 2.1(c)(iii) and 2.9(b) of
the Forbearance Agreement.

        2.2    National Accounts.    Notwithstanding anything to the contrary in
the Forbearance Agreement, iPCS hereby acknowledges that Sprint shall no longer
be required to maintain separate and distinct "national account" programs,
including separate national account sales forces for its CDMA Products and
Services and its iDEN Products and Services for national accounts headquartered
in the Service Area. Sprint hereby grants iPCS the right to approve any
discounted pricing to any "national account" headquartered in its Service Area
that affects CDMA Customers in the Service Area, which approval shall not be
unreasonably withheld. This practice is consistent with the long standing course
of dealing between the parties. Accordingly, iPCS hereby grants Sprint a limited
waiver from Sprint's obligation in Section 2.8 of the Forbearance Agreement.

        2.3    General Motors.    Notwithstanding anything to the contrary in
the Forbearance Agreement, iPCS hereby grants Sprint a limited waiver from the
obligations imposed on Sprint by Section 2.3 of the Forbearance Agreement, to
the extent required to permit to enter into a national account with General
Motors and its Related Parties as contemplated by Section 5 of the Amendments.

        2.4    NASCAR Branding.    iPCS hereby acknowledges that Sprint is
permitted to display Sprint, Nextel, Xohm and Boost advertising and brands at
NASCAR events held in the Service Area in substantially the same manner as
Sprint displays such advertising and brands at NASCAR events held outside the
Service Area and that nothing in the Forbearance Agreement should be interpreted
as contrary to this acknowledgment.

ARTICLE III

TERMS OF GENERAL APPLICABILITY

        3.1    Limited Waiver; Duration.    Except as expressly waived herein,
the Forbearance Agreement remains in full force and effect. The limited waivers
granted herein shall remain in place for so long as Sprint continues to comply
with the Forbearance Agreement.

        3.2    No Release, Waiver or Modification of the Parties Rights and
Remedies in the Ongoing Litigation.    Nothing in this Agreement, or in any of
its terms, including but not limited to, the limited waivers granted in this
Agreement, shall in any way be considered a waiver, release, modification or
amendment of the rights and remedies of the parties as asserted in or pursued in
the Ongoing Litigation, nor shall it be considered in any way to affect the
rights and/ or ability of the parties to fully pursue their rights and/or
remedies as asserted in the Ongoing Litigation. Further, nothing in this
Agreement shall, in any way, be considered a waiver, release, modification or
amendment of the rights of the parties to enforce any order or judgment of any
court entered in, or to be entered in, the Ongoing Litigation.

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        3.3    No Breach of Management Agreements.    This Agreement, and the
covenants of Sprint contained herein, do not constitute an admission by Sprint
that it has breached, or will breach, any provision of the Management
Agreements, nor does this Agreement, or any of its terms or provisions,
constitute an admission by Sprint or iPCS as to the scope of any party's rights
or obligations under the Management Agreements. Moreover, the provisions of this
Agreement are not intended in any way to constitute an admission by Sprint or
iPCS that any of its actions under this Agreement were necessary to comply with
or avoid any breach of the Management Agreements. This Agreement is (a) being
entered into for the purpose of resolving certain differences and possible
disputed claims between the parties and (b) entitled to all protections afforded
by rules of evidence applicable in Illinois and Delaware (as applicable)
analogous to Federal Rule of Evidence 408.

        3.4    Entire Agreement.    This Agreement sets forth the entire
agreement and understanding between the parties as to the subject matter of this
Agreement and supersedes all prior agreements, oral or written, and other
communications between the parties relating to the subject matter of this
Agreement; provided that this Agreement is not intended to amend or affect in
any way the Management Agreements and any other agreements entered into in
connection with the Management Agreements.

        3.5    Binding Effect.    Except as otherwise provided in this
Agreement, this Agreement is binding upon and inures to the benefit of the
parties and their respective and permitted successors, transferees, and assigns,
including any permitted successor, transferee or assignee of the Service Area
Network or of the License.

        3.6    Governing Law.    The internal laws of the State of Delaware
(without regard to principles of conflicts of law) govern the validity of this
Agreement, the construction of its terms, and the interpretation of the rights
and duties of the parties.

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        IN WITNESS WHEREOF, the parties have caused this Limited Waiver and
Consent Agreement to be executed by their respective officers as of the date
first above written.

    SPRINT NEXTEL CORPORATION
 
 
By:
 
/s/ Charles Wunsch

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Name:
 
Charles Wunsch

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Title:
 
Vice President

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SPRINT SPECTRUM L.P.
 
 
By:
 
/s/ Charles Wunsch

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Name:
 
Charles Wunsch

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Title:
 
Vice President

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WIRELESSCO L.P.
 
 
By:
 
/s/ Charles Wunsch

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Name:
 
Charles Wunsch

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Title:
 
Vice President

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SPRINT COMMUNICATIONS COMPANY LP.
 
 
By:
 
/s/ Charles Wunsch

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Name:
 
Charles Wunsch

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Title:
 
Vice President

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SPRINT TELEPHONY PCS, L.P.
 
 
By:
 
/s/ Charles Wunsch

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Name:
 
Charles Wunsch

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Title:
 
Vice President

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SPRINT PCS LICENSE, L.L.C.
 
 
By:
 
/s/ Charles Wunsch

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Name:
 
Charles Wunsch

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Title:
 
Vice President

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iPCS, INC.
 
 
By:
 
/s/ Timothy M. Yager

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Name:
 
Timothy M. Yager

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Title:
 
President and CEO

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iPCS WIRELESS, INC.
 
 
By:
 
/s/ Timothy M. Yager

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Name:
 
Timothy M. Yager

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Title:
 
President and CEO

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HORIZON PERSONAL COMMUNICATIONS, INC.
 
 
By:
 
/s/ Timothy M. Yager

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Name:
 
Timothy M. Yager

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Title:
 
President and CEO

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BRIGHT PERSONAL COMMUNICATIONS SERVICES, LLC
 
 
By:
 
/s/ Timothy M. Yager

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Name:
 
Timothy M. Yager

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Title:
 
President and CEO

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Exhibit 10.56

ARTICLE II WAIVERS
ARTICLE III TERMS OF GENERAL APPLICABILITY