The same systems operates in France and they are very hot if the flight plan is not closed after landing.
Ther are a number of pilots flying in and out of airfields that have no aftn and some have no ATC and all these pilots should know the importence and the reason when and why to file a plan and how it operates and to activate when airbourne also the importence to close the plan on arrival.
This is the UK we are talking about and the system is
NOT the same. I don't know why but there it is. There is no concept (with the one important exception mentiobned above) in UK ATC of closing a FPL and it just confuses matters for the original poster if people keep saying it. It's all in ENR 1.10.