Your description is probably a lot simpler than mine.
BUT!!!, I think in your case, it’s still achievable since it sounds like a case of one set of From/To dates. In my case, I have hundreds or thousands of rows that need to find a related set of data within a date range that varies for each of the hundreds/thousands of rows. So in reality, my situation seems different from yours.
However, to achieve what you want, if you can add single value columns to your task table, then you can populate the From and To date column value across all rows using single value columns. Then with an IF column, you can run a comparison to see if each row fits within that range and return the number of units if it’s within range, or return zero if it’s not. Then you can rollup the result of that IF column. That way it will only count the units within that date range.
So I tried your trick but I am stuck on how to use IF ELSE COLUMN using two separate date columns. Wish there was an option of using “and” and “or” in glidetables, so I would have done:
If “PRODUCTION ASSIGNED DATE” is on or after “DATE FROM COLUMN” and “PRODUCTION ASSIGNED DATE” and is on or before “DATE TO COLUMN” then show “Number of units”. and then I would have rolled up that value to get sum and count.