They are indeed valid to Croy - SPT have a map on their website showing the validity.I believe it's valid to Croy, so you could get an Edinburgh to Glasgow shuttle to Croy if a 365 worked it, currently an 8-car 365 set seems to be operating the XX:30 departures from each end which are non-stop Glasgow Queen Street to Croy. A short trip admittedly, but about the only way I can think of getting a 365 on a roundabout ticket.