Taking a sympathetic view to Blue Air, I imagine they need to make substantial decisions now as to where aircraft will be based over S19 and have a pretty good idea of their summer schedule. They might wish to leave room for minor changes later but when passengers expect a lead time of a few months between tickets going on sale and a flight date, they can't wait
Any pulling of flights has to be done 2 weeks in advance anyway, and with little obvious sign of agreement between Westminster and Brussels, it's getting close to crunch time for small airlines operating 7th freedom routes between the UK and the EU27