Lets you use the monthly per‑day rate M/MD for a partial month when the lease lasts only that single month.
Example: 6 days in a 30‑day month with D=$50, W=$300, M=$650 → Daily=$300, Weekly‑hybrid=$257.14, Monthly‑per‑day=(650/30)*6=$130.00. This can make short rentals very cheap, so it’s usually left off.

Allows monthly per‑day M/MD on partial months only if your lease contains at least one full month.
Example: Sep 18 → Oct 2 (13 days in Sep, 2 in Oct), D=$50/W=$300/M=$650. With this ON: Sep Weekly‑hybrid=$557.14, Oct Weekly‑hybrid=$85.71 → Total=$642.85. With this OFF: Sep (M/MD)=$281.67, Oct (M/MD)=$41.94 → Total=$323.61 (often too low).

If the lease later extends and now includes a full month, the engine re‑rates earlier partial months with M/MD and issues a credit on the next invoice.
Example: Initially Sep 20–30 (11 days): Weekly‑hybrid=$471.43. Then customer extends to a full October. We re‑rate September to (M/MD)=(650/30)*11=$238.33 and credit the difference $233.10 on the October invoice.

Guarantees a month’s time charge never exceeds the monthly rate M.
Example: 30 days with D=$50, W=$300, M=$1200 → Daily=$1500, Weekly‑hybrid=$1285.71, but the charge is capped to $1200.