If I’m on a LGW A321 in seats 1a/c and it switches to an A320, instead of keeping me in 1a/c it spits me out and doesn’t reallocate any seats. I have no idea why as it’s the right hand side that’s affected with no row 1 on the LGW 320s but the left hand side never changes. Recently and to make matters worse, the EF alerts haven’t been working properly (aircraft or seat alerts) so I had no idea I was seatless until I checked. So yes, check regularly and never rely on EF - I do pay for EF but sometimes, I have no idea why and the same goes for SeatSpy which has been woeful recently.