Yep, it's awful. The last year or so has been worse than the slam-door era for me (I stated commuting in the early 90s) - even taking into account the main strike periods and the occasional catastrophic delay we'd get through things like lineside fires etc. Passenger numbers must be hugely...
Delay repay is usually sorted within 3-4 days in my experience - the 20 days is presumably a 'just in case' thing.
As for the the OP's ticketing experience, I had a similar experience with my daughter but she needed air travel not rail. I was in the US and she was in Scotland, but within 10...