This is bizarre – the fields are definitely not changing, and in the db I see the keys are all the same. Even further if I simply change the field type back to “repeater” from “group”, my data reappears…
Additionally, if I try to add new data in this state, it does not show up on the frontend. And in the backend, validation is totally screwy – subfields that have no validation required fail validation for being empty (and don’t have the red asterisk).
I suspect this tampering just totally confuses some part of ACF…
