They are backing it because it keeps us in the customs union at least until we can agree a longer term deal with Europe so its the best they can hope for (apart from remaining obviously) A no deal exit is so bad any deal that keeps us going under current trading arrangements whilst we work on a longer term plan looks attractive By the way can someone explain to me in words an I can understand why leaving the Customs Union is desirable. Note the transition deal keeps us in the customs union but takes us out of the juristiction of the ECJ for all new issues which is one of the red lines met We already have good trade deals in place via the EU for most of our trade and I dont believe for one minute we can do better ones outside the EU other than in a few small areas When the likes of Rees Mogg and Davis state how easy it will be again just remember how easy they told us leaving Europe was