The Bowling Mom rules basically hasn't changed, but there have been slight variations to account for the actual number of RBs, or for special leg formats in some seasons.
One way to see this is to track how teams decide, and what they are shown saying on camera (and the viewer knowing what that team's RB balance is at that moment. It's been years since Phil has described the rule on camera, but if you track the teams week by week, it's pretty clear the rule remains in place.
You have to be aware and pay attention to what teams say in reading clues, or in conversations on camera/ The editors still let us know about these things, but rarely is it Phil doing a stand-up or voice-over of the change.