Jubilee Line staff on this Forum?

There are but it is up to them as to whether or not they wish to reveal themselves.

I work on the Jubilee, why do you want to know Croydon?

Indeed, our partner, the Met line [doffs cap in respect]

I don't work on the jubilee line but I do know that
*trains go to charing cross quite regularly, if there are weekend engineering works south of green park, all passengers get tipped out at green park, the train goes empty to charing cross, reverses and heads back northbound and then goes to it's booked destination.
*trains will also carry out this proceedure when there is service distruption.
*trains are taken there for driver training.
*trains are also taken there when filming is taking place there, for example when creep was filmed there.
*And finally, if the service is late running then they can also terminate at green park then send the train to CX aswell.

As far as I know, no trains are booked to run to CX in the regular timetable, but it is still used more frequently than you would think.

The only reversing points that I know of (apart from green park) are Waterloo, Canary Wharf and North Greenwich. Not sure if they can reverse east to west at London Bridge. Think its west to east at London Bridge.

Just a thought, are Willesden Green and West hampstead only used for reversing west to east? Could an eastbound train be reversed back towards Stanmore at these stations?

You can reverse W-E at London Bridge, but it involves a main line shunt, so it isnt an everyday occurrence. No timetabled move, strictly used only when there is a huge gap in the Eastbound service, primarily after there has been an incident and trains/drivers are in the wrong place.