Correcting a typo on a post that has been shared via multisite

Today, I shared a post across 15 websites via Multisite and then discovered a typo on the original post. I corrected the typo on the original post and then went through the 15 sites one by one to correct the typo, and much to my surprise on about half the Multisite websites the typo was already corrected. Do you know of any explanation for that? Is there a way to correct a typo across a series of Multisite websites without doing so one by one?