Looking again yesterday, I see that the trains will be going past Bolton to Manchester, after which you need to get off and catch the train back to Bolton, thus adding an hour to the 45-minute journey - each way. Needless to say, I've called that trip off as I've no wish to spend 3.5 hours travelling to and from a beer festival that's less than 30 miles away.
Instead I've suggested we go to the excellent Wigan Central, Wigan CAMRA's Pub of the Year and a finalist in the CAMRA National Pub of the Year competition, which should be good. A more than satisfactory replacement trip, I feel.
I wrote about this pub in our local paper (and on this blog) in May 2016.