In the UK, VFR flight plans, and IFR flight plans files below the level at which London Control is interested in handling traffic, get delivered to departure, destination, and nobody else enroute.
If you address a VFR FP to some enroute Class D unit, they will usually toss it in the bin because you are not landing there so they don't need to know. If you call them up, they will write out a strip for you (or the electronic equivalent) there and then. A prior-filed FP makes no difference to them.
It's different in say France, where all flight plans seem to go into one database which is accessible to any ATC unit.
In the UK, all flight plans go into some database from which they can be fished out if you go missing (and somebody has reported this), and they also go into some "national security" databases used for keeping tabs on traffic crossing the borders.