thanks! It doesn't seem to be working for me.
I've added the same site address and List or Library to both first and second steps and have selected the "trigger window start token" as per your screenshot.

and followed your same steps for the condition. I did swap out "true" in the second line to "Yes" as the milestone column either says Yes or No. When I did a test run, and noticed the flow didn't work, I tried to add in "true" as per your screenshot, however that didn't help. I also tried to tick both boxes under the And, however that didn't do anything either.

I've also followed the "Send an email V2" step as per your screenshot. Did a test run and changed a due date for a milestone "yes" in the MS list I have linked and I haven't received any emails. Not sure what I'm doing wrong here.