[iggldiggl]

> The deep tube lines will all get variations on the 2024 stock

I think that's a bit optimistic. Right now, the only thing that has confirmed orders is the replacement for the 1973 stock (Piccadilly line). The same order also has options for further trains which would cover the Bakerloo, Central and Waterloo & City lines, but somebody still needs to come up with the money for it.

For the Bakerloo line trains (1972 stock) that's probably going to happen, since those trains really are getting long in the tooth now, but for the Central/W&C line stock (1992 stock) there's currently a refurbishment programme underway, so depending on how that goes, those trains will probably continue running for a while further.

That still leaves the Northern and Jubilee lines (1995 and 1996 stock respectively), whose replacement trains, whenever they might happen, will probably need a new tender – it could be that whatever train gets selected then will be a close relative to the 2024 stock, but I don't think it's automatically a given.

And the Victoria line – that one only got new trains in 2009, so those will continue for quite a while further and will be the last ones due for replacement on the deep tubes.

[tialaramex]

That's a good point especially about Victoria, by the time a 2009 stock train is at its replacement age the "new tube for London" design is probably going to look pretty archaic and budgets are always too tight to make a replacement early. Who knows, by then TfL might actually have a "driverless train" plan for these lines which makes sense.