AEU 757s are not ETOPS certified hence why the Canada flying went else where when the last of the 737s left LGW last season.
You mention that the 737's have gone from AEU, but their website still advises they have Boeing 737-700, do these not have the range to fly to Deer Lake?
Astraeus Website and the CAA are listing 737's in there current fleet. See
G-Info