I also got the email... They cancelled my GRX-LCY on 26 June and LCY-GRX on 31 August, which makes me think BA is simply leaving GRX for good... as a Granada resident who frequently visits London this is really bad news (Easyjet flies to Gatwick but both the frequencies and times are noticeably worse, in my opinion). What's worst, it'll somewhat affect potential tourists (like the OP) who will now have to go through a hassle in order to reach the city.

For the OP, there are definitely plenty of options with Iberia via Madrid (flight time between Madrid and Granada is under an hour) and that's still my preferred option. However, you can also consider flying to Málaga and there is a direct coach service between Málaga airport and the city of Granada. Not ideal but a solution that'll only cost you 2-3 extra hours. Good luck!