Thanks Rickjq. I'd followed out the 'restore default controls' sequence days ago with no difference in performance. And I don't get how you could follow out step 4 above before re-updating the firmware in step 5. I also don't have a drawer full of smartphones at my disposal, so...'use another smartphone' simply isn't an option for me. Did you have any success??
AnafiPilot1: I brought the SC3 to work yesterday & re-soldered the USB contacts even though they appeared solid. I also tried a different USB-C to lightning cable last night - no change whatsoever.
I'm firmly convinced it's a firmware update flaw that Parrot has to fix asap. The AppStore claims the latest FF6 revision is only a week or two old - what did Parrot do to it??