Yes the reach will grow but the stack will also shrink. People focus on the reach number in isolation but you need to consider both reach and stack together for sizing. I just did a quick sketch in solidworks and the reach grows about 7mm with the fork sagging 40mm. Not massive.
For example, 2 bikes, bike A has reach 436mm, stack 650. Bike B has reach 450mm, stack 620. Wich bike is bigger?
Answer - they are the same. Bike A will just require fewer stem spacers.