When I had the P0521 one code, I was seeing around 13 psi of oil pressure at hot idle. I replaced the sensor once, CEL came back on about 100 miles later. At that point I changed the oil and filter (Mobil1 5w-30 and ACDelco PF48E), and the CEL stayed off for over 3000 miles. We'll never know the outcome though, because that's the point that I pulled the engine for DOD-delete.
So yeah, changing the oil could help. You could also switch to Rotella T6 5w-40. May help retain some pressure once it gets hot.
2009 PBM GT
Under the Knife Again
Wiseco Pistons, K1 Rods, Johnson Lifters, BLP Keep Hatin' PDS Cam, Roto-Fab, BLP Ported Intake and Throttle Body, Kooks 1-7/8 long tubes, XForce Varex Catback, ZL1 Converter, Camaro Trans Pan/Filter, GXP Brembos
Breyton GTS-AV Wheels, 6k HIDs, Holden Steering Wheel and Paddle Shifters, Eibach Springs, 35% Tint
Tuned by Day Tuning