Over the past couple of weeks I've noticed Transavia France 737s passing up the irish Sea on Transat flight codes, around bed-time.
Managed to track one last night and it was operating TSC94 from Paris-Orly to Trois-Rivieres, Québec ( which FR24 has now filled-in ).
http://fr24.com/2014-12-08/22:25/12x/TSC94/4fed4bfCouldn't find much online about these flights except that at least one Transavia aircraft ( F-GZHD ) has been painted into Transat colours. However last night's one, F-GZHJ, is still in the Transavia toothpaste-tube livery.
A sad omen for 2015, when the 737s start to displace the Transat A310s
