Not sure how familiar you are with the underlying technology running steemit, but a TL;DR will put you at the following: Only a certain amount of information is read/write, until a period of time has passed (the second payout, or 30 days), at which point the content is essentially read-only. 

This is in my mind an unfortunate aspect of steemit, but with the current technology setup it's required to prevent ballooning of in-memory database calculations. I REALLY hope to see fixes for this in the future -- but for now, steemit blog content unfortunately has an interaction limit of a month.