I thought I'd try and create a complete list of new units that are due to be ordered and where the existing units are due to end up, so if anyone knows about units I've missed off/don't know about then feel free to mention them. TPE 350s - Releases 185s to be cascaded internally to provide extra capacity. LM 350s - to provide extra capacity. Thameslink Desiro City - Releases 377/5s back to Southern. Were due to provide extra capacity but new order may provide that extra capacity instead. Possible could provide 313 replacement or allow some units to be cascaded to SWT - Releases 319s to Northern and FGW. Should allow internal cascades to provide extra capacity, as the 319 cascade replaced a new DMU order due to provide extra capacity needed by 2012. However, it's possible a small number of units could be cascaded from Northern/FGW to other operators. St Albans Tram-Train - Replaces 321s. Future of 321s uncertain. Sheffield-Rotherham tram-train - Unlikely to replace any existing services. However, there may be a possibly if any 3/4 car workings are used on heavy rail via Rotherham that they get switched to other services. Crossrail - Releases 315s and 365s. Future uncertain and will likely depend on future electrification projects. Merseyrail EMUs - Replaces 507/508s. Likely to be written off. Extra Scotrail 380s - Future of replaced units uncertain. Transport Scotland says they will provide extra capacity. However, number of extra units very high compared to passenger numbers and rail magazines suggest some 158s will be cascaded south of the border.