You say it's 32C outside. Googling around, it seems like the avg July temp around Georgian Bay (this time of the year) is 25C. Is that right?
The way that I understand how Flexible Monthly works (which may be incorrect) is that it creates a watering interval based on historical weather from your area (and adjusts monthly). So if your area is running 5C+ hotter than normal right now, then I don't think that Flexible Monthly accounts for that.
I use Flexible Daily. I like how it does adjust for the current weather and how easy it is to see the data that the Iro is using to make its decisions. I attached an example of the data from the main zone of my front lawn.
Anytime the Iro is not watering when I think it should, it's been an issue with the data, not the software.
Typically this happens when my yard gets less rain that what's reported from the weather station a few miles away. I also had an issue the root length was incorrect (new lawn, they weren't as deep as I thought). This caused the Iro to let the water level in the grass drop lower than what it should because based on what I told it, the roots extended down further. Bad data (on my part).
When I notice a zone is dry but the Iro doesn't think it is, I simply go into the app, tap into the zone, tap on Moisture Level, hit Adjust, and hit Empty. Easy-peasy. Zone gets watered the next day.
The last two weeks have been running about 10'F hotter than normal, and the Iro (on Flexible Daily) has been keeping up with it well. If you look at the graph below, you can see the Iro has watered 4x in the last week. Normally this time f year, it only waters once, maybe twice. But with the unusual extra heat, the Iro is watering more.