I'm really interested in hearing from experts here what leeway there is for additional services running alongside those currently running?
As a none-expert, may I add some thoughts?
I think there are three single line sections - between St Budeaux and Saltash, Liskeard and Bodmin Parkway, and St Erth and Penzance. The current 30 minute service is probably about the limit though those sections - especially as the through services have to be knitted to fit all three single line sections. But for Truro - Par, really no problem stepping up to a 15 minute service that I can see; might be signalling / headway issues. Whether such extra trains could be synchronised to the single line to Falmouth running every 30 minutes, the offsets of the eastbound and westbound mainline trains necessitated by the remote single line sections, and the single line via St Blazey to Goonbarrow and then on to Newquay I question / doubt.
Expert comment welcome.
and the pre C19 level of service provided by GWR▸ and XC▸ ,
I'm going signal double amber not green ... I am not convinced that post-covid services will rise to pre-covid levels, or levels that were planned at that time. There is both a risk and an opportunity there - the risk that trains which are doing more than simply adding capacity will be 'taken out', and the opportunity to put in something different and fit for the future.
Could any Open Access service also be possible, I think not?
Technically, it probably could be. Practically, it feels highly unlikely to me in terms of the financial model that would need to be found, the risk that someone would need to take to do it, and the utter off-putting complexity and roadblocks that seem to be thrown in the way of such proposals.
But ... we are in changing times. We hear talk of localism. We see some really good stuff from some councils such as Cornwall (and some less that helpful initial reports from our subnational transport boards). It is not beyond the bounds of dreams to have a Cornwall Metro, run by and within Cornwall / extension to Plymouth.