Still too far off really to say, but Thomas Cook seem to be basing an A321 all season rather than the A320 with the A321 just the school holidays.
Thomson pretty similar to this year except they will no longer have the late Monday evening Corfu service in the peak season but will fly to Gran Canaria in the afternoon all season instead.
BH Air will fly from July 21st until the end of September.
All other carriers don't have any flights on sale yet but so far this looks only very slightly better than this year.