Hi there,
I'm about 200m from the site! The ground has been like total concrete, but we have had decent showers last night, and it is quite overcast now with more showers due. If their ground is anything like my fields then it will be totally solid with a bit of a softer top cm that makes it really quite slippery. The rain just hasn't been enough to sink in properly and soften the ground up. Def a studs day for the ODE I think! Good luck!