Is it flat?
Ink a grid on the stone face with a sharpie, pencil lead will wash off with slurry. Do 10 laps on 600 grit paper dry, on a flat substrate. MDF is flat-(er), glass and marble & granite tiles are not, unless they have been flattened. Glass is easily flattened.
Once flat running through the grits is relatively quick. Getting to flat is the trick. If not flat, 600 grit paper will not get you there on a Translucent Ark.
It is not a question of time, you must have a quantifiable measurement. It will remove all the ink in 3-5 laps or not.
If the stone is not flat, the lower parts of the stone that are not finished, will come to the surface as the rest of the stone wears and those unsurfaced spot will ruin your pristinely polished bevel and edge.
It is much like a fully bevel set. If you do not have a fully set bevel you can not polish an edge that does not exist. 90 percent of all edge problems stem from bevels that are not fully set. Most of Ark finishing issues are from stones that were never fully flat.
You only need to flatten a finish Ark once.