Hi Jim,
Thanks for confirming the behavior of allowUpdates=True.
I just want to confirm I understand. So, there is not a way to block edits for specific fields in a repeat once a user has reopened a previously sent survey. Essentially, either all fields in a repeat can be locked or all can be editable, by using allowUpdates=True. Instead, a workaround would be to create a second app built on the same feature service, where I could set the fields I want locked to readonly (or remove them). And the field staff would be able to use this second app to query previously sent surveys in the existing feature service and edit/resubmit them, if necessary. Is that the gist of your suggestion?
Thanks,
-Erik