I called the medicaid office and they said just submit a change of address. But when I look at individual states online, it appears there may be some complications on moving. I am especially concerned that his SSI will be withdrawn, or require a lengthy application period. He needs that money for his regular expenses.
Does he have a case worker?
I would make double sure that all paperwork is completed, approved and processed to avoid a delay in his check. You're smart to get that done upfront. I know there are people around here who know a lot about this topic. I hope they will respond to you.
Really try to find out what the availability is for an identical programs are & if there is a waiting list BEFORE you all move.
Your son will need to apply & be eligible for Medicaid in the new state. Whether this is simple or easy will totally depend on the new state.
His SSI is federal so that should be unchanged.
States by & large limit state supported programs to state residents. Both you & your son will need to establish residency. I will suggest that you look into right now having all banking & direct deposit of income at a banking group which is in both states. Switching banks to get direct deposit done so there isn't a gap month is kinda dicey.....so you need to plan this out. Open up the new accounts for each of you (no comingling on accounts) with the old state address then right after he gets his check, he goes online to get direct deposit moved to the new bank. once you all move then you change the address to the new state.
Good luck!