While Bigpants' observation regarding flow isn't far from the truth, I will have to stick up for some of our Traffic Managers (and this is a very rare thing for me, I can tell you).
There have been some flow restrictions in place of late to allow for management of the inbound delay to London TMA airfields to a level that a safe dispersal can take place given the situation regarding our lack of a TC contingency plan (should the flood gods find it their want to vent their wrath again!!!).