Originally Posted by Viajero
AFAIK that is one of the few unswered (untested?) issues yet to be settled in this forum. If memory serves, there's no post in the archives reporting either success or failure. So, go on, try it and break new ground!
.. and don't forget to tell us the outcome.
The BKK Ta from whom I bought the ticket says no, this is not allowed. Will try it with BA and report back!
Thanks as ever for all the helpful comments.