With fare rises due in January by around 3% it must be time to look again at splitting your journey and buying two or more tickets instead of one. On Cross Country trains off peak tickets are valid from 0930 so you have to pay full price on the 0927 departure from Penzance, the 0925 from Plymouth and the 0927 from Exeter. Odd how these departures times from our three big centres are all just before 0930 !!!
You can get a cheaper fare by buying in advance or by splitting your ticket. An anytime return on the 0927 Penzance to Edinburgh direct train costs £433.95 in December 2019 but if you buy a single to St Erth, a single from St Erth to Penzance and an off peak return from St Erth to Edinburgh the total cost is £257.75 so you save 41% and you travel on exactly the same train !!! All tickets can be purchased at Penzance but you will not be able to reserve a seat for the whole journey and you must make sure the train stops at the station where you split your ticket. You will also have to make sure you leave Edinburgh on your return journey after 0930. A small price to pay.
You can make similar percentage savings by buying tickets from Totnes instead of Plymouth and from Tiverton Parkway instead of Exeter.