Since we are discussing the part of the thread title that states "TfGM plans for the future" (whatever that implies), I feel that we cannot be "off topic" and orders for additional rolling stock definitely falls under that reasoning.
At this moment in time, what is the current thinking on the purchase of tram-train units, which appears to form part of recent statements of Metrolink expansion. Will a third depot need to be constructed to allow for a rolling-stock increase or can the two existing depots cope?
1.) True, I just don't want to fall foul of moderation rules.
2.) Page 38 of the Draft Greater Manchester Transport Strategy 2030 (accessible
here) mentions development of a Metrolink "NGV" (New Generation Vehicle), which should also be suitable for use as a tram train.
I can't find any information about depots, but given there is a fair amount of heavy rail depot capacity in southern GM, perhaps TfGM could lease space in one (especially given their plans for Marple Rose Hill tram trains that would use heavy rail infrastructure in the Ashburys/Ardwick area).