Ah, I thought you were staying overnight on 25th already.
I'd prefer not to stay overnight in that particular week (Sept is better for that), but two possibilities I can think of - only you'll know what's reasonable:
- overshoot your ride down on 24th and visit Haynes in the afternoon, and then back to your digs. I would join you somewhere on the way down (you're welcome to come here, of course), and follow on the way back up to your digs, and then home
- stay an extra day (but that costs you) and I can come over on 26th. If I actually pull my finger out I could be over to you for 10ish, and we might hit two places. The Tank Museum is only 1 hour south of Haynes, and Beaulieu is 2ish. But then you have to get back up north too...