Ask HN: What is the average salary for a Head of Product in the UK?

I am currently negotiating my new position at work and I am being promoted to Head of Product at a fairly large company here in the UK.

We have over 7 million users, around 120 staff.

What would the average salary be for a position like this in the UK? The role is not based in London.

I am trying to judge a fair benchmark for my negotiations.

Thanks in advance for your help.