In my limited experience other airlines very often claim that the table published at time of flying is the table used. There is no advance notice of a change and there are no promises made as to future earnings. You might be able to get the points "as a goodwill gesture", but only as exception.

One exception I know of is SK that at least on point made promises that old bookings would count towards old table. IIRC, you still had to do manual retroclaim to get that, as systems were only able to count by the principle of "published table on day of flight counts".

I am happy to be disproven though!