For the past few times I have flown, a yellow warning message came up in the upper left portion of the controller screen saying something about "Infinite Focus Calibration Required" with a little yellow ">" symbol.
I couldn't find anything about what is required anywhere other than a post on this forum saying "follow the instructions".

My flights are over salt water, so I'm hesitant to get into anything I don't know about on a normal survey gig.

I finally had some time, went out a an open field set everything up expecting some sort of flight procedure to different altitudes, camera angles...

I had no idea what to expect.

Turned everything on, the error came up, I pressed the ">" and waitied for my impending instructions....

Nope

It said "OK" and the message went away.

Duh!

Wasn't having any touble with the P1 before, don't seem to be having any trouble now, have no idea what the calibaration squence calibrated.

I only know I didn't need to go out and set everything up

So, it turns out there is a required procedure to be carried out in flight.

I got the "P1 calibration required" message again, and this time it took me to a help screen that said to go into "Setting" for the P1 and find the calibration option.

Once you press that it tells you to hover above something with "multiple visually discernable features", then press the "Calibrate" option.

When I did, the camera blurred in and out several times, then said that calibration was complete

Did you swap lens before having the calibration message?

No, I only have one lens

It was a bug in the P1 Firmware that didn't save the calibration if you did it and also displayed the warning in the first place, that has been fixed now in the latest P1 firmware. It was so annoying!