Subset has drag features to fill subsequent cells with data or formulas. You can manually fill cells by selecting a range and pressing CTRL R to drag right or CTRL D to drag down.
Subset also supports autofilling, which is enabled because each block has defined rows and columns. Autofilling allows you to drag right to the last column, drag down to the last row, or drag all to the last row and column of the block.
Combine this feature with dynamic blocks such that no matter how dimensions of the blocks change, your formulas are filled out. This is showcased in the example below where Grid 1 is linked to the “CohortSmall” block and as the data changes in the “CohortSmall” block, the formulas are autofilled to the edge of the block as the dimensions of “Grid1” change.