Ordered 21 Sept 2021 when should I get delivery?
I think any answer people hereabouts could give would involve the question ‘How long is a piece of string?’.
What you could try to do is keep in regular contact with your dealer – albeit take any forecast of delivery dates with a pinch of salt.
Also sign upto any Vauxhall Mokka owner’s clubs/forums/facebook etc and see on there how long others are wating for your same vehicle.
Also on Facebook follow some of the Motability related groups as they have known Motability dealers who occasionally post if they have such as cancelled vehicles with short lead times or even in stock. I seem to recall a few months ago, one such dealer had a Mokka E available at short notice.
I don’t really think there is much else you can do in the current situation with vehicle scarcity.