Many thanks for all the reports, folks- very useful.
I was going to say it looks like things are settling in to a c.3-4 week lead time for double TP posting.

However….
I just checked my own account and my double TPs have just posted from a booking where the return flight was 10/11th March.
From my own notes, this coincides with the timing of posting last year which was generally Wednesday or Friday the week following the last flight.
Although, again from my own notes, I never had any bonus TPs post on a Thursday before, only Wednesday or Friday.

Final thing to say, these double TPs posted from a booking that was eligible at the time I made it (June 23) but would no longer be eligible.
Make of that what you will, but obviously good news as far as I’m concerned.

My only slight complaint (not really) is that I was starting to hope for a post-April posting with inaccurate dating which would have boosted next year’s total but I also wonder if that might have been the impetus for BA to get this sorted out.