[Msquared]

Wasn't sure whether to ask this in the 1LE forum or the Suspension/Brake forum. Asking here because it's probably specific to the Brembo calipers and this where the track junkies hang out.

I was doing a PDE event at World Wide Technology Raceway (formerly Gateway) today in my 2020 SS 1LE (all stock) and I suddenly lost my brake pedal completely. Luckily it was at a fairly innocuous corner and I was able to cut across it in the grass and come back on track with no damage.* Trundled back to the pits where we discovered that both bleeder screws (inner and outer) on the RF caliper were very loose and fluid was just geysering from them every time I pressed the pedal. We were able to screw them back down and they didn't leak any fluid. I topped off my reservoir and had no issues driving home.

So now the question is: why the hell did this happen, and how do I make sure it doesn't happen again?! For context, this is a 2020 car with lots of autocross use and 10-12 track days in its history. I last flushed the brakes before the SCCA Time Trial at Autobahn at the beginning of August. I competed that weekend, SCCA Solo Nationals, and a bunch of other autocrosses since then. There's no way I left those screws loose this whole time, or the failure would have happened a long time ago. This caliper is on the corner that gets the most cornering and braking load at this track, so it stands to reason it gets the hottest. Can heat cycles cause the bleeders to loosen and back out like this? Nobody I know has ever seen anything like this before. One obvious answer is "Tighten the bleeders tighter." However, I don't want to strip the threads in the caliper. What sayeth the forum members?

*Discretion being the better part of valor here, as there is a wall awaiting those who enter this turn too fast and push out of the exit.