This is actually a current issue that's being discussed because the transition fully relies on the miners to make hand off the transition because of the content

This is actually a current issue that's being discussed because the transition fully relies on the miners to make hand off the transition because of the contention with moving to PoS. One possibility is that miners will fork the chain, although that's not necessarily a huge concern because the community will follow the PoS chain. Another possibility, and I'm a bit fuzzy on the details, but it has to do with them re-mining the same block over and over so the transition block never happens (or something like that).