Yellowstuff pad delamination

[HughS47]

Was at a snetterton track evening last week and the recently new yellowstuff pads that I'd installed delaminated and we were left with backing plate pressing against disc.
The pads hadn't been difficult to install, had done approx 300-400 miles on the road problem free before going on track and one other trackday first. They didn't get excessively hot before failing either, they had felt 'wrong' from the moment we started on the sighting laps.

any ideas what might have happened? I've emailed the online EBC shop we bought them from to see if it was a batch fault with the manufacturing, but is there anything that might have happened?

As a final query, how do people bed in brake pads for trackcars that aren't road legal?

[HughS47]

The manufacturer are going to look into it. I've bought some more yellow stuff as replacements as I've had them on the car previously and been very very pleased with them. You only ever hear worst case scenarios in here though, but I suspect ebc have had their issues with some pads in the past.

If it happens to this next set then I'll be changing the DS2500s.