I mean, I believe there's gonna be overhyping after any news and a consequent dump/correction. (Well, except after the EEA announcement I guess because that was huge).
It's probably a good strategy to keep ETH and sell after the POS change/pump then. Could you mention a few coins that switched to POS and had this pump/dump? Also, I'm not very knowledgeable as to whether or not STEEM is POW or POS...