The free plan still has costs associated with it that Glide absorbes. There no way of knowing if someone is testing features or exploiting them, so limits are in place for a reason.
It’s most likely that the first 10 rows, or first 10 accessed rows get geocoded, and none of the others. It’s 10 total. Not 10 at any one time. I don’t think your filter plays a big part in which rows get geocoded
With that said, have you considered a free trial to try out all features without limitation?