In February 2014 I've booked a ski holiday for my son and I with Esprit. I am flying from Edinburgh to Chambéry on a Sunday and the flight details show BA with a BA flight number. It's probably operated by CityJet LCY fleet as the timings look right:-
The charter timings are:-
BA4541 Departs EDI @ 08:10 Arrives CHAMBERY @ 11:30
BA4542 Departs CHAMBERY at 12:30 Arrives Edinburgh @ 13:50
BA have an EDI-LCY @ 16:45 that can't be operated by an inbound fom LCY as the first northbound on a Sunday leaves at 15:10 arriving in EDI at 16:30.
I'll be happy with a Embraer E190SR.