If you're very quick, you could get Nematodes off the internet, and all the instructions come with the packs. They kill off the chafer grubs.

We treated our lawns at the end of August, as it has to be done in a certain temperature range.

Good luck!

If there are any starlings in the area, try putting down some feed on the lawn. If you can get them interested they will go over your lawn like vacuum cleaners pecking through the turf to winkle the grubs out.

I had rooks and badgers digging up my lawn to get to the grubs. I'd want to warn Charlie about the terrible mess they made of it, and I wouldn't put food out in case they decided to come back! Eeeek! :-O