The only difference to the 15" model is the slightly larger screen.
I wouldn't be surprised if Apple drops the 15" model completely and replaces it with the 16" for the exact same price. Starting at $2399 for six cores and $2699 for eight cores.
In the UK, we sadly have an absolute imbecile as prime minister, whose dangerous actions will likely drop the pound even further against both dollar and euro, and Apple usually re-calculates the prices according to the exchange rate when a new model is introduced. With the pound close to $1.15 and dropping, and 20% VAT, the UK prices in pound will likely be slightly higher than the US price in dollars.
Well certainly this is possible but with Apple charging 5000 bucks for iMac pros and 1000 for stands I remain somewhat pessimistic that we’ll get any legit upgrade for “free”