Give users the option to keep using the "familiar" interface, but without any "support". I suspect many user actually require "support" because of interface changes.

IME, observing other users, it is the forced change that is offensive to some. They do not complain about "lack of support" (many want to be self-suficient and do not want to keep asking for "support"), they complain about changes that they see as unnecessary and that will just require more effort to learn.