I’ve been following this thread since I was having the same issue with pressure overshoot during my shots with my Elizabeth. For me, it was happening on every shot so I decided to open the machine and clean out the OPV. I was relieved to see that my machine, 2022 V3 model, had the OLAB OPV which appears to have a better design than the original, according to previous posts. I found that the internals of my OPV had corrosion and possible scaling so I cleaned it up as best I could and applied a thin layer of McGlaughlin Petrol-Gel Lubricant (I didn’t have Molykote III available) to the moving parts. I ended up removing the entire valve because I couldn’t get all of the internals out and thought I could do a better job of cleaning if I could take it apart. When I reinstalled, I used Teflon tape on the small threads. Getting the silicone tube back on the other end was tricky but it felt tight afterward so no cable tie required. I did this today and it seems to fix the problem and will have to observe over the next few days. I set the OPV to 10 Bar to compensate for pressure drop between the pump and group head, with the intent to achieve 9 Bar at the group head. The video link at the bottom is after I reinstalled the OPV with the blind basket installed.
Pressure after cleaning OPV