well what will monarch do for all those sharm runs if the 757s are phased out? the 321 is a very poor substitute for the 757 on many MON runs, but particularly for the ever increasing number of flights to Sharm from Northern airports in particular, the 321 will have range or payload issues many times, will pax get there, maybe but all there luggage too? if the 321 is chocka full and winds are blowing be a struggle for a fully charter config 321 to get back from sharm, unless they are planning to reduce the holidaymakers luggage allowance to say 10kg? haha.
Sorry but the 321 cannot do for monarch what the 757 can. So Monarch might think to keep those old birds a little longer! lets hope so.