I find the BA holidays helpline excellent to deal with. Also when you have to change flights I often find the new flights move up to J so more avios.

The deposit option is great especially as they have lowered the amount you have to pay since COVID.

Also you can get some surprisingly good deals, especially Eastern European destinations in winter. I got 5 nights CE in PRG with 4* hotel for £530 in November from GLA. £50 deposit too.