Can anyone please explain playing up an age level to me and who actually guides this and decides how many kids can play up? Can kids play up if it is a "pure team?"  Can players play down if it is a minor pure team? Does it matter if the team is Tier I vs II? Is it USA Hockey, local league (AHF, NJYHL, AYHL, etc) or based on the organization itself (Black Bear). Just looking to clarify what is a murky mess and understand. Would love a link to an actual policy on this :-)

Not looking for benefits/downsides to it. Not even for my kids. Just trying to understand the drama around our rink and get a clearer picture of what our teams will actually look like next year.

AAHA District decides. Kids can play up a classification (mite to sq, sq to pw)if district approves, must be signed off by rink hockey director. No 12 year old can play up to Bantam, ever. Any kid can play up within Sq and PW without district approval. 2 Major kids can play down on minor team Policy on District website.

Not true on 12U playing up to Bantam.  I always thought that was the rule as well, but I'm aware of a couple in AHF the past two years... no idea how it got approved

AAHA rules

https://cdn1.sportngin.com/attachments/document/46cf-2853178/2023-2024_Rules_UPDATE_10-20-23.pdf

There are always exceptions.  I know of one 2011 who played up (Bantam Minor).   There may be others.
Maxwell Prudovsky - Stats, Contract, Salary & More

Almost every AAHA "Rule" has language that allows an exception based on some grand exalted minister of hockey's judgement or decision, for those enterprising enough to have a favorable audience or influence over said grand exalted minister of hockey. 

... after all, it is the exceptions that make the rule, eh? ....

Sometimes, "It's the Science" just isn't good enough.