When to move money out of stock market

I’m 54 years old with around 310K in S&S ISA, 500k in pension, house payed off. I am thinking of retiring in around 5 years. Should I already be looking at taking most of my money out of the stock market? I know I should probably de-risk but unsure when it is necessary to do this. I was thinking about moving all my S&S money into a cash ISA, but also don’t want to miss out on returns over the next few years. Any tips?