I've just failed to get the information I was trying to get from the
London Underground Customer Service Centre.

I did get other information which may point readers in a useful
direction.
It seems the last A stock will run a special service on September 29.
Tickets go on sale from the London Transport Museum at forty pounds from
September 3.

The information is not yet on the LT museum web site.
Tickets can be bought at the Museum on POTS://020 7379 6344.

The trip starts at Moorgate about 10.00 and ends at Wembley Park about
16.00, after visiting every Metropolitan station and the proceeds go to
charity.

I would like to know which train numbers currently run using A stock.
With that information, I can find the trains using
http://cloud.tfl.gov.uk/TrackerNet/PredictionSummary/M

It may be that there is no answer to the question.
--
Walter Briscoe