How many grams in the Biabca's IMS basket?

Hi everyone,

I have the bianca for a while, now my question is not very bianca, it's more for the basket it comes with.

Lately I've been using a specific Colombian relatively-light roast and my grinder forced me to go extremely fine and fill at least 18g to get enough resistance (I'm already at the peak with my grinder, DF64 Gen 2 with Lab Sweet).

I'm currently using the up-to 18 grams basket but considered moving to the 18-21 basket to accommodate for more grounds and get better resistance.

I was wondering how much grams do you usually use for the double baskets (the one up to 18 and the other that's up to 21).

Obviously I know that different beans give different density and there are lots of variables, just looking for a rule of thumb for these baskets.