Well, my July has filled up with Rides including a 275 km ride with a local club that I really fancy the look of the week before. I think I'll take my chances and just ride as I see fit, the miles I have put in so far this year make me think I'll be fine. I rode a 200km + 75km to the event and back before PBP in 2015 before riding down to Paris from Vernon with a load of others who had ridden from the ferry in Dieppe (and some rode the UK side as well) so I really don't think it will be an issue.
To make things better I also have the whole week before LEL off work so there will be plenty of chance to rest up.