I got to have a quick chat with a Jubilee line driver at Stratford
yesterday night about the TBTC ATO system, I was curious to know how
the trains implement a stop at Stratford Staff Halt if there is a
request from staff at Market Depot.

The driver told me that the line controller has to be informed and a
request stop will be implemented in to the system once the train
departs West Ham, once the train arrives at the Staff Halt the driver
opens the cab door and that stops the train from restarting, once the
cab door is closed the train can continue.