While we're trying to interpolate the ER's future by focusing on the seasonal 25% swing, that's completely irrelevant. The only thing that will drive displacements or not is the super double secret ER/75 retirement plan. There's really no straight answer to that right now. Depending on who you ask (and what hour of which day you ask them) the ER fleet is being extended with dramatically slower retirements, or we're fixin' to cull a mass quantity of 75's in a 2 year period. That makes a huge difference in the company's decision to displace or not, which is always a tough one during a period of hiring and transitioning at a relatively rapid rate (not to mention possibly a little *gasp* growth?!?!?!)

You just can't get a srtaight answer out of anyone on this subject. And even if you do, it'll change in a week anyway. In the company's defense, they probably don't know either and are simply enjoying the "flexibility" they have with a very good and capabile, "paid for" fleet type with lower capex as they surgically analyze each and every flight it does with incoming newer AC.