eFXdata reports that Societe Generale Research discusses its outlook for GBP.

"In real terms, sterling trades about 12% below its 27-year average, and 14% below its average level since the collapse of Bretton Woods. It's 8% above the all-time low. A persistent current account deficit and a collapse in the UK's pre-GFC relative rate advantage don't suggest a poor trade deal with the EU would get sterling out of its post-GFC range, but still struggle with the idea that it can trend lower and lower, even on no deal. If EUR/GBP breaks parity, it will only be sustainable if the ‘real' EUR/GBP rate is anchored by higher UK inflation. If taking all this to heart, we should expect GBP/USD to trade to the mid-1.40s next year IF there's a deal, and bounce after an initial fall to the mid 1.20s, if there isn't" ," SocGen notes.