You're correct, I misread Norways wind LCoE of 44€/MWh as offshore, though it was onshore.
The publication you linked projects a 44% cost reduction until 2025, though. Given UK's listed offshore LCoE of $125 in 2018, that would be $70/MWh for the UK. The trend looks linear, but if we conservatively assume it only falls at half the rate after 2025, it will be at $51/MWh once the first Rolls-Royce plants come online in ten years.
The publication you linked projects a 44% cost reduction until 2025, though. Given UK's listed offshore LCoE of $125 in 2018, that would be $70/MWh for the UK. The trend looks linear, but if we conservatively assume it only falls at half the rate after 2025, it will be at $51/MWh once the first Rolls-Royce plants come online in ten years.