Question regarding hours worked per week during OPT


I am working part time for a company on my OPT. I work more than 20 hours a week most of the time. However, for some weeks, I have worked less than 20 hours. It is because, I work for small company, and sometimes they do not have sufficient project that I can work on. I am applying for STEM extension soon. If USCIS asked for paystubs for my current work, how do I justify my case? What are the options for me? For instance, some of my paychecks indicate hours worked less than 40 (in two weeks period). I continued this job immediately after graduation (I was on CPT for same job for 4 months until graduation). I had reported the current employer properly to DSO when I started working on OPT.

Thank you for your help.

Edit: I looked up in my timesheet. So there are 3 weeks in separate instance when I did less than 20 hours. Will 3 weeks be counted as unemployment ?

Did you get an answer to this? Did USCIS asked you anything?