There are still flights ex-LHR available tonight that, with a quick overnight layover en route, get you to NCE by 815a or 900a Saturday morning...
- LH2481 to MUC tonight at 815p, quick 7-hour turn in MUC, arrive Nice 815a
- AF1181 to CDG tonight at 745p, 9-hour turn, arrive Nice 915a
- LX339 tio ZRH tonight at 805pm, 8-hour turn, arrive Nice 905a
I'd be jumping on
something. Might even be fun. Is there nothing at all that suits you outside of your original plan A? Because BA/T5 is where Plan As go to die.