Shoot, that's not good .. Hope you find something else quickly.
Don't think this is going to help either .. Originally I thought we were going to South Wales, Brecon beacons, but we're not, it's North, near Flint! I guess this isn't the best news for you ... but I'd rather say now than spring it closer to the date.
So it would help us both if someone could pick the trailer up and get it to or nearer Bristol! .. they'll either need a Nato Hitch or use the one with the trailer, bolted to their chassis cross-member or drop-plate.
Many apologies, I did this with the best intentions ..