How on earth do I get REASONABLY PRICED train tickets from Sheffield to London?!?
It’s a question of Yield Management, just like airlines. The train companies know that they can fill a train on Friday and Sunday at £50 a ticket just as easily as they can fill them at £6 a ticket, so that’s precisely what they do. Same applies for busy times like Easter, Bank Holidays, Christmas and New Year. If you want a cheaper ticket, you need to avoid travelling at busy times. Late morning on Tuesdays, Wednesdays and Thursdays tends to have reasonable availability for cheaper tickets and reservations for Midland Mainline are currently open up to Christmas Eve.