These transitions were made because for 10 seconds we were just testing whether the SMS was leaving or not. Also, these of these 4 stages are most of the "passing", that is, it should be that they skip.
Here I made a test order
https://our-store.com.ua/55259/. But the SMS went away twice.
2) Yes, there are a lot of conditions, but I have a similar "branch" where there are even more conditions and there are no problems.
Not long ago, I found a pattern in which SMS does not go away: if changes were made to the process and immediately click on the "Prepayment" stage, the SMS does NOT go away. And if you first press the "save" button, and then to the "Prepayment" stage, then the SMS goes out correctly. Nowhere and at no other stage is it necessary to additionally press the "save" button. This is just about the third question.
3) There are no such rules in these actions. Moreover, if you go back and make changes again and do not press the save button, the SMS will not go away again (((That is, at the "Prepayment" stage, in any case, you need to press the save button.