As with the Design Classics Prestige Stamp Book(PSB) Machins pane, the Charles Darwin PSB has some surprises, especially as the PSB stamps are printed by De La Rue as the ordinary counter sheets are. I don't think we've had a 5p - or indeed any Machin - quite this colour before!
The Machins from the Darwin PSB are printed by De La Rue in litho and are shown on the right.(The normal sheet stamps in gravure are on the left).
Remember these are simultaneous scans: if the 'old' stamps don't look like yours, make some allowances for your monitor and my scanner! The new ones are still different.