Boltar wrote:
Given that one crossrail branch heads into woolwich , will the trains
be dual voltage or will they put 25KV overhead on the DC lines there?

There hasn't been a 25kV EMU built since, probably, the 322s that isn't
dual voltage under the skin. Modern power electronics means that dual
voltage units are completely trivial, basically a question of bolting on
a few shoes, and isntalling version X of the software rather than version Y.

Robin