Since we’re sharing anecdata: I also have the $20 month plan for codex, and I hit the five hour limit after about an hour of work every single time I open it. I use it for personal side projects primarily in the evening after kids are in bed, so my strategy is to launch it about 4pm and send a simple prompt to prime the 5 hour window to end at 9pm, start working about 8pm, and then I can use up the existing 5 hour window and the next one by about 10pm.