How do you know when it's time to switch from your current grips and use your new grips? Is it the 6-months rule even though your grips feel good? I got a new pair of grips to break in (same size, same style). Cuz you know, anyways it's good to have 2 pairs of grips that are usable. What do you all do?

I switch grips around 6 months too, and then keep the old pair as the backup when they're still good and usable. One of my teammates had their dowel part come off one of their grips and another had the stitching part of the grip come off and make it unusable so yes, it is really good to have a backup pair of grips! For practice and for competition too. If your grips don't feel good earlier than 6 months, then it's time to get new grips earlier - like if the leather part of your grips feels slippery and you don't have enough 'stick' on the bar.