"Very variable" must be the answer because it's totally leisure orientated. Football matches, concerts, beer festivals and the like with fine weather and all the usual disruptions caused by unit and staffing issues to compound the results.
An example. Northern's 11.15 from Sheffield to Manchester was a 4 coach 150 and looked to have very few seats available at Dore when about 60 more boarded. Many would have been standing from there. Nice day, lots of walkers for the Peak District, large group of well behaved lads armed with alcohol plus families going to Manchester and beyond. Typical Bank Holiday cross section.
However TPE normally run a 6 coach 185 over that section 3 minutes earlier but not today due to rest day working issues. Many end to end travellers will have been aboard the Northern service. If TPE had run I suspect a 3 car Northern would have been busy, but adequate. As it was Northern had been considering running 6 car 195s.
On a sunny Saturday the peak service of the day might have been an hour earlier. It's very difficult to plan for leisure!