I would not get too excited. Most of the £20k will be swallowed up in legal fees I fear.
But there is some good news; this case, although it settled out of court, did have a preliminary judgement handed down. When it came to valuing the value of an image, the creator's valuation was accepted, and the defendant's derisory offer dismissed.
The judge also remarked on the technical challenge and exclusivity of access. I do not think it unreasonalbe to reason that Underwater images will fall into either or both.
This is useful as its now a case that can be referred to in others.
And I suspect the £20k is a thin end of a much bigger legal bill for the defendant. I'm speculating here, but the total bill may well be double and some.
It really is cheaper for all to seek permission first. Or settle quickly.