I was driving the 1F46 service at 16:27 and at Ebbsfleet I forgot to to change to 3rd rail. Amazingly I was able to set off and continue to Gravesend as if I was on a catenary.
I don’t think that’s a bug. I believe that in real life, this is possible due to the momentum you get before the overhead runs out but you won’t get any farther. I seem to remember Matt saying in a stream that he did a similar thing in the other direction and tried to get all the way to St Pancras without raising the pantograph but didn’t quite make it.