I'm going to come across as rather childlike and indecisive (I'm 50 btw!) but I've never been good at negotiating social situations and have got completely out of the habit over the last year.
A friend has invited a group of 6 of us to have a get together in one of her fields (we are rural). She's asked everyone to come at 4pm so she can unlock the gate. The walk from the gate to the picnic spot is quite long (about 10 mins) so we all need to be there on time.
When we first arranged the gathering I said I would be working until 5 and would come after that, I didn't realise the gate would need to be unlocked. Obviously I can't get there by 4. I don't know whether to ask her to walk back to the gate which will inconvenience her quite a bit and will be annoying for her to walk for 20 minutes after having sat down with a glass of prosecco for an hour before, or say I can't come, or cancel work which will mean pissing off my client and losing money.
The gate is too high to climb.