Originally Posted by
Jzlerner
I'm not doubting that you have more experience than me and definitely more than the ground staff, what I'm concerned about is getting turned away with that case due to the staff thinking or being told it's not possible. As aforementioned, I cannot afford to leave this case behind so need assurances.
If you absolutely cannot afford to not have the additional bag with you on LHR-TLV, then you need to think about another possible situation: what if your JFK-LHR flight is badly delayed? AA will try to rebook you to minimise your arrival delay at TLV, but it could leave you with insufficient time to get home, get the bag, and get back to LHR in time to drop it before the LHR-TLV flight. In that situation, would you deliberately delay your LHR-TLV flight, too? You may encounter some resistance if you insist on that being rebooked when it would be a voluntary change.
Beyond that, you're probably not going to get any more or better assurances here than you are getting from those of us who have done this and similar things repeatedly. Would you accept an answer from an FTer who's a BA insider and knows what check-in can do? We do have some regulars who fit that description.