I guess one of the aspects where I've been quite spoiled as a UK-based EXP is award availability with BA. It's never been as good as *A availability via UA, but typically, so long as a flight had a bunch of seats available, at the very least, business class award availability would appear a couple of days beforehand. Lately, even monthly award maps have been looking very empty indeed. I know there's school holidays in the UK right now, but it has started to look like you can no longer count on BA availability via AAdvantage for a last-minute weekend getaway, even if you're very flexible with destinations. Is this BA or AA turning off the tap?

more so, I think it s the school holidays...
sorry but the only way to grab award travel now is to keep looking.... there might be some holds that were not ticketed that become open.

I hope you're right (and Expertflyer is very useful!). And retiring the 767s has decreased capacity on a number of routes.

I'm sure that what you are seeing is a reality for you and the routes that you need but I have not seen a particular drop for the routes I watch with a possible exception to some Saturday and Sunday flights next summer. One explanation could be the collapse of Thomas Cook.

Just as AA�s move toward multi-tier mileage prices for any given cabin and a more explicitly revenue-based program for redemptions using AA miles has hit the ability to use BA points for AA flights, the same sort of throttling of availability of BA flights using AA miles is to be expected. BA has already trialed some revenue-based award redemption pricing, and I�m expecting that this is just the beginning of BA copying AA when it comes to redeeming airline loyalty program points.

In other words, I am expecting that the redemption pricing/availability is going to get uglier than it is already even when using BA points for BA flights. And it won�t be all that better when using AA miles for BA flights.

It�s more than just a Thomas Cook impact.

You may well be right for the future but its not consistent with what I've been seeing now which is what the OP was asking about. The Thomas Cook impact, if any at all, is now.

I don't see why - they both come out of the same inventory

Same inventory bucket doesn�t necessarily mean same availability/pricing; rather it is being increasingly decoupled.