I must admit that I didn't knew about the info of the phases. When I bought them, they where lampropeltis mexicana alterna, but on a forum I go regularly they said that there where name changes in Lampropeltis. They told me that mine is Lampropeltis alterenata blairi. This all was more than 3 years ago.
They are 6 (the male) and 7 (the female) now. That's why I wonder if he's capable

Like I said, I saw him rubbing against her many times last year, but I never saw them attached to each other and had no egg development whatsoever... I would already be happy with infertile eggs