-toots whistle- BELIEVE IS HERE.
Okay, so! Let's talk seasons. First of all, as some of you probably guessed, you don't advance to second year through a FULL YEAR of coursework. That would just be complicated. Thus, this roleplay is going to work without months and only seasons. (Months are canon in the universe but to save time we only will have seasons for advancement purposes; therefore, you can still use terms like the date.) Currently, it's spring (which is more like the Japanese school schedule) and I'm not sure yet if I want two seasons to equal enough classwork to advance or four seasons. Probably two, but you'll hear more on that later.
Now, for the juicy stuff: holidays! Instead of having individual holidays, we'll have seasonal, week long celebrations. This makes it a lot easier to work with some holidays that are human-religion based. (Hanukkah? Christmas? NAH FAM.) During each week of celebration, depending on the beliefs of each Pokémon, it is common to spend time worshipping legendaries that either fit with the season or just your general religion. (AKA, you can celebrate something like Celebi during spring, or Arceus year round. IDC.) The festivals occur at the end of the month, and while students get a small break, they will have important final exams around those times!
Now, when we think of the globalization of manmade Pokémon, keep in mind that all of our Pokémon are civilized, technologically advanced creatures. They, like humans, have cities--radios--ovens--all of that delicious stuff we wouldn't be able to live without today. Except, here's the thing... Pokémon care more about the environment than we do, first of all. Thus, while with the reasoning that Pokémon like Magnemite, Klink, and Trubbish could still exist, certain ones will either be less common than others or new species. Grimer could probably be more of an accidental science experiment gone wrong than a gutter-dwelling Pokémon. Pokémon in this universe reduce, reuse and recycle! My second point is that, since Pokémon are the animals, you know that fancy rule about using meat substitutes? Well, we're not gonna force Miltank into slaving away in the dairy industry. However, a lot probably have their own little farms and such for producing milk and making some cash. Milk DOES exist in the universe, (as well as lovely substitutes like almond milk and--oh no, run Exeggutor, coconut milk) but it is not a harmful setup to milk-producing Pokémon. Not everyone has to grow up and be a farmer! Follow your dreams, little cattle. ANYWAYS, you'll find out more about the seasonal celebrations soon enough! It's only the beginning of spring.