Letting the grass grow ha saved me hours of work over several months, and I have loved the wilder look, but meadows do need managed and it's time to cut them now.
Mouse nests and little mouse routes are revealed after the first cut (with hedge trimmer - I can't manage the strimmer). If the little creatures only had the sense to stay outside!
It's really important to remove all the cuttings - you get more wild flowers if you keep the fertiltiy low...Good ecercise!