checked in for a flight NUE-CDG for tomorrow - expertflyer shows C1 - still I am travelling in business class with my mother (silver) and my sister (explorer on a separate ticket). I could not put my sister or my mother beside me. the seat next to me was blocked (set to unavailable) automatically - no matter where i moved myself to. the only way I could put myself next to my mother or sister was to place them first and then select an adjacent seat. so the seat blocking is also implemented for checkin and not only for advance seat reservation (same issue)