The views expressed are my own, worth what you've paid for them, are not on behalf of anyone else and not those of any company I work for etc.
Yes, there are sea locations thagt are closer such as Southend or The Blackwater in Essex. Even Gildensludge is preferable. The 120 miles is to the Norfolk coast which is the closest reasonable sea diving.
We have been looking at overnight stays next month and the price is shocking. Finding anywhere near a decent diving location for less than £100 a night is difficult and most are much more than that.