We absolutely loved Diggerland in Rochester, Kent! We all went here as a special day out during Nik's annual leave. It was part of our "staycation" (we couldn't risk a 2 week quarantine both working for the NHS), we did think that Kalyan would be the one to enjoy it most but we all thought it was awesome! I hardly got my "big" camera out so I was glad I had my new phone with me for plenty of selfies and videos of the action :)
It's just over an hour drive from Uckfield and well worth it, we spent all day there! If you don't know about it, kids can basically drive and control real diggers! They need to be over 110cm for most (or can ride with a parent) but a couple had 140cm height requirements (to reach the pedals I think). The twins wanted us to join them for most rides anyway but they did do some alone and certainly took over controls even when we were next to/under them.
At the moment they are restricting numbers so it's not too crowded which means shorter queues. This doesn't mean they don't still take a while though as they have to clean and wipe everything in between so you will still have to wait a bit.
The park isn't massive but is well organised and there are plenty of friendly staff. The rides are all brilliant, Priya can't even decide on a favourite but has mentioned going up to touch the sky a few times (one digger lifts you 50 feet in the air)! Kalyan's favourite was the digger below, he loved digging deep holes and dumping the soil in a pile to the side.