Hi
@fisherdvm
Your initial post was confusing to me, the discussion, following it, has gone all over the place. Clearly, it would be in your best interest to have a good understanding of how your computer(s) work and you should pursue that goal. I believe the fact, that you are a DM and a Solo Diver, made it more difficult for people to understand how you could not be more familiar with your computer. If you can not read your computer, you should take action to remedy that or get a computer you can read.
Your questions made me curious, so I perused the Mares Puck Pro manual:
Safety Stop: I don't see that the safety stop can be turned off or changed. It is 3 minutes between 10-20 feet. It is
not mandatory, and can be skipped. It is displayed with SAFE and a time countdown
Deep Stops: I don't see that deep stops can be turned off or altered. Deep stops are generated as "you approach the no deco limit" The deep stops will be one stop for 2 minutes
or two stops for 1 minute. I could not determine why one of the two strategies would be chosen by the computer. I believe the answer to your initial post is that the first two stops were the recommended deep stops and the third stop was your safety stop. The deep stops are
not mandatory and can be skipped. When in no deco, the deep stop is displayed as DEEP no deco. If you are in deco, the deep stop is displayed as DEEP DECO.
Deco: Deco stops are
mandatory. When in deco, it will be displayed as DECO with a depth, stop time, and total ascent time. Whereas the uncontrolled ascent lock out can be disabled, the missed deco stop cannot. If you miss a deco stop and surface, you will be put into violation gauge mode and will be locked out for 24 hours. The computer does have an erase desaturation option in set up. I don't know whether that would work after a missed deco stop or not
Good diving, Craig