There is no concept in the UK (with one important exception*) of 'closing a FPL'. Yes, we are different, the reasons lost in the mists of time. As Chilli says, I don't know why overseas departures get exercised over this as SAR is not their concern. When it became possible to land outside of a customs airport we regularly got requests to cancel FPLs. We tried to explain at first but then gave up and just said 'Roger'.
As for putting 'REQ ARR TO whatever' we wouldn't even see it at our place. Auto FPL processing, Electronic Strips . . . Oh dear.
*The exception is if you have to nominate an ATS unit as your 'Responsible Person' when landing out in the sticks. You must notify them within 30 mins of your arrival otherwise SAR could be commenced.