Over at ADSLGuide they have noticed that the BT availability checker has some new information added to it.

Now the checker will tell if an ADSL cease is on the line, this is placed on the line when ceasing an ADSL connection. This will be helpful for ADSL users who cannot migrate to another ISP and are waiting for the line to clear before they are able to order a new ADSL connection.

The checker is on the BTWholesale site, here, but as most ISP checkers are linked to the same data then this should be reflected in those also.