Did think on that, but will need to make good and level to fit new floor in time so not wasted. A bag of cement and sand isn't much, seems easiest.
You could always put a silicone bead around the current cutout and maybe a layer of something so that if you need to pry it up down the line it'll be a bit easier.
@hugo7 started
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Did think on that, but will need to make good and level to fit new floor in time so not wasted. A bag of cement and sand isn't much, seems easiest.