Bad news: I couldn’t find a way to coax a return fare out of a train company for the combination of London / Glasgow and back tickets I want - even though the OJP suggested they exist.
Meh news: not *that* much more money.
Bad news: there are no seat reservations available for the way back at the moment.
Bad news: Southern aren’t confirming engineering work until about a month before, which interacts badly with reserving anything.
OK news: I can ride to a working station for most likely combinations of Southerning of this end’s trains.
Good news: a sensible priced reservation was available for the sleeper to Scotland.
Good news: the impenetrable nature of bike booking on Virgin means I have a bike space on the awaker getting back again.
Which, combines to the good news that I’m getting four and a bit days of riding to and around Jura, Islay and Arran in May.