Is this irregular?

I've been a regular person when it comes to AF but since my husband and I have been TTC since December 2015, the dates have changed from 28 days to between 31-35 days. the maximum I've waited is 35 days now I don't know what to expect this month.

P.S: I have not been using any pills prior to this time but I have just moved to a new city in January. I expect that my body should have adjusted to the new environment by now.

Has anyone experienced this too? What are the chances that the fertile window from this app is correct for me?