You guys have got to be kidding. This is the most hilarious thread I have read in a long time.
To think you would divert an aircraft because the cabin has not been cleaned up shows a lack reality. Every airline has some form of communication when on descent in the event that some persons don't recognise the change in sounds, pitch etc. If the pilots did not communicate the fact they were on descent and the cabin should be ready for landing means they would have to shoulder lots of the blame. But to go to Manchester - you have to be kidding?
At the end of the day, most descents take nearly 25 to 30 minutes. Even if all trays full of food were on everyones laps, a crew should be able to pick them all up and stow them in quick fashion. Bad luck if the punters have not finished eating. Say 15 pax per crew, how long would it take for each person to collect 15 trays each, stow them and perform their normal duties.
If a crew cannot do that, then I would hate to see what they would be capable of. Didn't a BA 747 have all 4 engines go out not long after departing Asia for Aus years back due to volcanic ash. The crew managed to clean everything up and do a ditching prep in no time at all. Don't think they would have said hang off the ditching until the service has finished.
Get a grip on the real world.