Will,
My 4 yr old in pot tree supposed to be DK has about 10 large brebas this year.
Last year (when I thought it was LSU gold) there were 22 total but smaller brebas that were yellow on the outside and amber on the inside.
They tasted good.
This year they are just as yours; one week earlier, larger with thick white layer between skin and the core.
I picked it up because it split.
Tasted just OK, lacked flavour, was not sweet enough either.
Perhaps it needed few more days of ripening.
The tree is loaded with main crop that will abort pretty soon.
All of the above makes me think it is a DK.
There is another tree I have; 3 yr old that has two dozen brebas not ready yet.
Breabas are of similar shape, similar colour, big difference is that it will start setting main crop in August about a week after breba is gone.
Some of the main crop holds, majority will abort.
Is that a DK too?