It would be more reasonable if, after providing appropriate notice, the vendor were to invoke a hold period only if the customer fails to pay a support bill. Then suspension of support shouldn't be tolerated. In an equitable agreement, the remedy must match a vendor's loss but isn't intended to give it any additional benefits or create additional risk or hardship for a customer. A vendor's idea of good faith may be very different from yours. Both parties must define and agree to what's being said in such good-faith provisions.
Clarity beats faith every time.
Under this standard vendor boilerplate, the vendor also retains all other remedies, such as the right to go to court and obtain an injunction. Don't be inclined to give a vendor multiple remedies for a single infraction on your part. The remedy should attempt to make a vendor whole for a single infraction and nothing more. Here's a better way to write the provision - one that gives a vendor adequate protection but isn't overly restrictive for a customer. Licensee shall pay vendor the fees set forth. . . .