Jazzyvee,
The closest you will get is the show on September 2 in Saratoga, CA which is within a couple hours of Alembic's Rohnert Park HQ. But you'll be traveling there from Fresno (south) the night before, and then traveling on to Lincoln, CA (NE) for a show on the 3rd - plus, the 3rd is a Sunday...
The question you should ask is; where are you staying the night of the 3rd and where do you leave from to head back to the UK. Most likely that would be San Francisco's airport SFO which has direct flights to the UK?
If you had the opportunity to delay your departure by one day and found yourself staying near SFO, that puts you a little over an hour's drive from Alembic. But still not easy because public transportation over here would not be easy and you do NOT want to take an Uber or you'd spend every penny made on the tour.
You'll be that close ... but it's not easy to get there.
That tour is going to be a ton of fun!
Jimmy J
