Fuel Pressure Issue Related To Altitude

I wanted to see if anyone else with the 912iS has ever had issues when they turn off fuel pump #2 where the fuel pressure decreases for a second and the engine hiccups. I have narrowed it down to only happening if I wait to turn off fuel pump #2 until much higher than my usual pattern altitude. After reproducing the issue the second time I decided to intentionally try and reproduce it but instead of turning off fuel pump #2 I turned off fuel pump #1. This time everything was fine. I then turned back on fuel pump #1 and then turned off fuel pump #2. I didn't get a hiccup this time (maybe would have if I gave a longer wait before turning off fuel pump #2) but I did see the fuel pressure go down momentarily. I'm wondering what would be some good next steps to help try and diagnose this and if anyone else has run into this as well. Thank you