My province has gained exactly 500 peasants/tick for at least the last 7 ticks, despite being thousands of peasants underpopped. While I am heavily drafting, the draft only amounts to about 300 solds/tick. Moreover, my Houses percentage is fluctuating each tick thanks to lots of incoming Explored acres, so I don't believe this is a matter of just happening to luck into an identical growth rate.
Is there some sort of hard cap on peasant growth? I'm SURE I've seen ticks of 2K+ peasant gains during EOWCFs before.