I also use mini blinds for my seedling labels. All the seedlings from one cross have the same # as yours do Mona. My crosses are labeled like 11-01, 11-02, 11-03 and so on. 11 is the year they are planted and the other numbers are the cross number. I record the cross and the number just like you do. (11-01 pod parent x pollen parent) in a spiral notebook, I never put this in the computer because I don't trust computers not to crash, and I also need the notebook in my hand when I go to the seedling beds.
If I have 10 seedlings of one cross they will all have the same # until I decide I will keep one then I will add an A to the last two numbers on a mini blind (11-01A), take a photo and put that new # (11-01A) on the photo name. If I see a second seedling from the same cross it will be (11-01B) on the mini blind, take a photo and put the new # on the photo. The # in the note book never changes you only use the notebook to identify the cross. All my seedlings are in the ground but the same system will work for pots.
