eFXdata reports that CIBC Research expects shallow GBP rallies after a potential Brexit trade deal.

"As the clock ticks down, the question remains: Is there sufficient time left to conclude a deal? We still expect a deal to be reached, but we will need to see a degree of statecraft (political concessions) in order," CIBC notes. 

"Our central case scenario remains a deal being brokered before month end, notably ahead of the final scheduled EU Parliament session of the year, from December 14-17. However, a deal is not the end of the process. Rapid ratification, within necessary protocols, risks becoming a concern," CIBC adds.