As others have said, next to no one will be wanting to catch a .uk.com domain.
I can't think of any company (and after a quick check couldn't see on a couple) who even track these to see if they are dropping.
The main reason being is that you buy a .uk.com is just a sub domain of uk.com so no one in the domain world really wants them.
As Lovekraft said, DomainMonster is your best bet here for a back order.