what counties in texas are mmp mandated
MMP. MMP participation varies from county to county. 5. Can a TexanPlusÂ® HMO dual eligible member enroll voluntarily in a Medicare-Medicaid Plan (MMP)? exanPluses,TY Â® HMO members in Harris, Dallas and Tarrant counties who are dual eligible may enroll voluntarily into a Texas MMP beginning March 1, 2015.