Old sprinkler controller has no wire to P but two wires to C

I got my Wyze sprinkler controller a few days ago. I tried to install it today but found that my old Richdel 508 sprinkler controller has wire to P but two wires to C - one is common and one is common wire from outdoor model. the power for the controller is wired to a transformer then to system board. Anyone knows how to wire it on the new Wyze controller?
Here is the photo

Did u get it to work? I too had two white wires as C and plugged one into the C of the Wyze and the other white wire to the other C terminal. So far so good.

I did the same like you did. I have not turned on my irrigation system and tested the Wyze control yet due to the weather here is still very cold sometimes. your info is a good news to me. Thanks.