Cycle length question

Hannah • TTC #1 since January 2014
Hi, I hope someone can help? 
​I have been off the pill for 3 months now. I have had signs that I have ovulated in my last two cycles which is great but I've noticed that my cycle
​Length has changed from 32 days month 1, 30 days month 2 and AF has just arrived today making my last cycles 26 days! I'm now wondering what I should I put down as my cycle length in my settings for glow? This cycle I ovulated days earlier than glow predicted (I guess that's why I've had a short cycle?) but I'm worried now I'm going to be missing my fertile days if glows predictions are out because my cycle keeps changing?! Guess we'll just have to BD every day this month in case?!!