OK, so the repairs are done and I reassembled the model for a final check. When I switched on the radio, both ailerons went UP in a flaperon configuration. They still moved in opposite directions as ailerons are supposed to, but just started from a position about 1/2" above level. That had never happened before. Eventually, I realized that I had inadvertently flipped the flap switch on the Tx.
This was actually a lucky accident since it revealed an oversight on the radio setup...and pointed to several other things that I should check. I wouldn't want to accidentally hit the flap switch in flight so the flap action needed to be disabled, which was simple. And this reminded me that I need to check and set the "failsafe" positions for the servos and also add a throttle-cut setting.