I think EZY will keep the 321s. GB were already in the process of replacing nearly all the 320 with 321 over a period of years because the 321 was found to be much more profitable on the core gb routes like MLA,AGP,FAO,TFS,PFO etc. Of course the aircraft is only profitable if you can fill it, which GB were able to do through the power of the BA name and the repeat business from the regulars who own property at these destinations.