The issue with fluidity in county squads is the undue pressure it puts on players, maybe that's what people want from these children. You could have a lad training all year, travelling 3-4 times a week to Cork, their parent finishing work early to get to to Cork for a gym session every week, then 2 weeks before championship they are dropped for a lad who played well in a school game? Or a young lad has a niggle or is sick, and feels they have to train or else they get dropped. Or a lad dropped because the soccer season is finished and a good lad is now available. Awful pressure and situations to put on children.
Pick the panel February, ride it out for the 4 months after that. Let the panel be the panel. If a lad isn't good enough to make the 36 man panel in February, he isn't going to pass out 20 of them in the next 2 or 3 months.
And if he is good enough, then he will make it at U20 level and we can all give out about the minor manager here.
But fluid panels in season are not nice for those involved.