there was a time about 2 or 3 years ago when there was a rule introduced stating that once TC had issued a release the a/c had to be airborne within (I think) 10 mins. Wasn't really adhered to at the time. Saying that it doesn't seem t be an issue nowadays anyways... and as mentioned above, the Solent guys do a fantastic job and are pretty busy... making a mockery of certain 'band 5' approach units at TC...