I doubt if easyJet will turn BRS into an Airbus base as they've only just converted it to 737NGs. There is tons of room to park a few more overnighting 737s now the GA aircraft are South Side. I think BRS management are well aware that their spectacular x million passenger growth is primarily a factor of its easyJet traffic.
BRS runway need not present an unmanageable problem to a 757. There are numerous combinations of engine power and weights that mean that performance problems can be got around 99% of the time. When they can't just bus them to Cardiff once a year.
Cheers
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