Fixed Schedule Watering 3x as Much as Flex Monthly?

I’ve been using Flex Monthly since I installed the Rachio years ago. However, I have heavy watering restrictions (can water 2 days a week) and I have been wondering if Fixed might be a better choice.

I created a new Fixed schedule and have been using that for the last few weeks. It has been watering significantly more than the Flex Monthly schedule and I’m trying to understand what’s happening.

Here’s an example of the two schedules:

Flex Monthly:
Watering Duration: 6hr 14m (374 minutes)
*Setup so it can water Tuesday/Saturday but system was only watering 1x a week on Saturday

Fixed:
Watering Duration: 8hr 28m (508 minutes)
*Same Tuesday/Saturday setup, but is watering consistently on Tuesday and Saturday

Fixed is watering 134 minutes extra per watering and twice as often. That’s roughly 2600 extra minutes of watering per month -or- nearly 3x as much watering!!! Both of these schedules have smart cycle turned on, the same weather intelligence and same zones turned on.

What is going on? Why is the fixed schedule recommending so much extra watering with the same settings?

Bumping this up for visibility. Anyone have any ideas here? I’ve since manually reduced the watering times for the new schedule to avoid a $1k water bill, but still wondering why there’s such a huge difference.