No, I am almost certain that this would not affect your sales.
Although I personally pay my eBay fees several times a week, I would think that the majority of sellers only pay once a month when they have to.
eBay sales have been erratic for a few months now. Huge fluctuations, often coinciding with major bad and good news in the media.
We average about 35 items/day on eBay but have had a couple of days recently where there was not a single email in our inbox. No sales, no payments, no questions. Then, we experienced days with over 100 emails sitting there in the morning.
I have never seen it like this in all my years on eBay. In total, sales are fine on a monthly basis but, as I said, huge fluctuations.
Bernie