The idea was originally that they'd move up after rotating out of modern. Matt reaffirmed the stance and made it clear on the recent town hall. It was basically said "this is what we're doing unless you pass a proposal to tell us not to do it." Some people are upset about it, so we got a proposal to hopefully settle it. If someone wants to run a different proposal, that's okay too.
To make it absolutely clear:
If you want things to stay as they are then you'd vote "yes" as that is saying "don't change anything."
If you want it to change to where all cards move up to the same PP level as Chaos Legion when they leave modern, then vote "no" as that is saying to follow the plan per Matt.
RE: SPS Governance Proposal - Don't Change PP Values