I wanted to draw your attention to this post in the BA Forum:
https://www.flyertalk.com/forum/37256452-post26.html

TL-DR it talks about the difference in availability between Point of Sale, and Point of Commencement. Lufthansa Group and now BA have moved to PoC so availability displays in Expertflyer using PoS are now no longer accurate.

Feature Request - please can you add in a field that allows you to specify the PoC for an availability search.

I fear that without this, EF will become increasingly unreliable for us European folk that travel LHG and IAG airlines. I’m sure AFKL will follow suit in the not too distant future.