My Duotone Unit bladder just popped in the middle of a session. Pressure was within specs and wing was always carefully folded.
It looks like the stitching may have come undone for some reasons causing the bladder to expend out and burst.

For a full tear, I would have resorted to get it fixed by our local repair person, however she is gone for over a month and since it is only the stitching that came undone, I am considering sewing it by hand using polyester thread (92) and follow the holes pattern. I would probably start-stop about an inch out on either side and maybe tape the LE from the inside with Dacron tape after stitching.

Has anyone ever done this? Any tips to share?

warranty in my opinion.

Warranty should not happen. I had a leading pop from another brand, warranty not an issue.