Mobiles.co.uk actually have some decent deals:
Pixel 9 256GB, 500GB data (ID Mobile), £748.76 (less £150 enhanced trade in, so £598.76).
Pixel 9 Pro 256GB, 300GB data (Vodafone), £934 (£734 after enhanced trade-in). Slightly cheaper on ID Mobile.
Pixel 9 Pro XL is £70 more than the regular Pro.
Pixel 9 Pro Fold 512GB, 500GB data (ID Mobile), £1,488.76 (£1,188.76 after enhanced trade-in). Free Pixel Watch 2.
My "man maths" is now telling me the Pixel 9 Pro Fold is a decent deal here. £1,188.76, less £100 from selling the watch, less ~£650 from selling my Honor Magic V2 leaves £438.76. 24 months of airtime would cost me roughly £240. So it's a £200 upgrade...? Save me from myself!