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I think it is related to posts with recent payouts. I checked other accts and all have the same results. Anything recently paid (maybe in the past 24 hours) are earning higher rewards.

I checked someone else’s post with a reward from 3 days ago and the reward was less; similar to the Tim Cliff post from this acct.

Stopped researching since it’s past my bedtime. Let me know if you find out anything @simplymike!

Reasoning explained by @crokkon. 🙂