Probably, though I think the body can forget and need to be retrained eventually, as in revaccinations.
What’s interesting is that most T1 diabetics still maintain some minimal detectable c-peptide production even decades out, which suggests that there are still a few beta cells hanging around. Saw this in one of my parents’ copies of “Endocrine Today” or some other medical trade rag. Not clear why, in the absence of all antibodies, these shouldn’t start to regenerate. Of course, there are several unknowns - if there are some small quantity of antibodies (below the detectable levels with the current titers), how long beta cells take to regenerate/reproduce, what kind of a beta cell mass you’d need to have around to start noticing it, and whether taking exogenous insulin (which, as we know, suppresses to some degree production of endogenous insulin) has the effect of slowing/preventing beta cell regeneration. On those questions, ask someone who actually has a clue