Help! Is that mold?

Hi everyone, it's my first time posting but I've read many great insights here before - thank you!

I'm creating a new gluten free starter using King Arthur Measure For Measure GF flour. I did not see activity of any kind for the first 3 days of feeding, then I completely forgot to feed it the fourth day, and today (the 4th day) I went to feed it and it was covered with very light fuzz. Is that mold or something else? Assuming I should now start over but wanted to check here first.