It's not the bag drop that's the issue, it is that check-in must be completed 1 hour before departure. It automatically shuts at that point, hence the phone call to get you on. As per BA.com the 1 hour deadline applies to these airports: So yes, they did you an unusually big favour - bisous and all that, I hope you enjoyed the Gallic charm.
Amsterdam, Amman, Antalya, Barcelona, Berlin (Brandenburg), Brussels, Cairo, Dalaman, Florence, Frankfurt, Istanbul, Istanbul - SAW (Sabih Gokcen Airport), Lisbon, Madrid, Milan (Malpensa), Naples, Palma de Mallorca and Paris