It may just be entirely random.
There have been some suggesting it is based on titan score but I find this flatly unbelievable given how quickly some alliances progress and there’s no way to accelerate that.
Also alliance score appears to matter not at all either, see Extra Spicy Nuts.
As near as I can tell there’s some percentage to move up, move down, or stay the same (actually you can move up two on wins, or down two on losses) but when you’re on 1*'s the move down selection is pushed off the table. How this is affected by prior wins / losses I don’t know if any, and it’d be nearly impossible to correlate unfortunately without an amazing amount of data which we will never, ever get.
Also I would have to go back and look but I know we’ve gotten 4-5 9’s in a row before, so 5 1’s isn’t out of the realm of possibility.