Bloomberg reports that currency strategists are delivering a reality check on how far the pound rally can go if the U.K. and European Union finally clinch an historic trade deal.

The general consensus is that much of the optimism is already priced in, with the currency up more than 9% since the end of June while the relative cost of hedging pound weakness over the next year at its lowest since March.

The pound will probably advance to $1.37 if the U.K. and European Union finalize a trade deal on Christmas Eve, according to Credit Agricole SA.

Canadian Imperial Bank of Commerce says sterling could touch $1.3715, although it recommends selling the rally.

“The upside is pretty marginal now,” said Adam Cole, RBC Europe Ltd.‘s head of currency strategy. “Taking the bookies’ quotes as a proxy, the probability of a deal rose from 50% at the weekend to 90% yesterday, so I think the repricing is largely done.”