It's not 1:1. See here: 10*320 days are mapped to 356 days. In this case, it's a 1.1125:1 ratio. The page also answers question about seasons etc.
GM events use the dates like on the Wiki page. You can use this to do the same conversion manually.
But yes, generally, game time is completely insane. It's almost impossible to RP time because it's somewhere between being 6 times as fast and 0.89888 times as fast as normal time. I usually have it somewhere in between. (sometimes a bit slower, sometimes a bit faster...)
Thanks for the pointer, I remembered some of those details that from character creation. But still, is using exact timing in the game appropriate? The clock in the window kind of suggests to do it (It would be useful if current game month/date would also be shown somewhere. Not necessarily in the window, but for example on some board, like in the library, etc.).
Having these specific details of the calendar (10 months, each having 32 days, making the whole year last 320 days, four seasons of 80 days, because of the cultural heritage of the people coming from the surface) gives some interesting insight into the Yliakum universe. On Earth the relation of month to the year is artificial, because year measurement is actually the result of the solar cycle, while the month is the result of the lunar cycle. But since lunar months don't sum up to the solar year exactly, the year is divided into approximate intervals (for example like 30/31 etc.).
So in Yliakum having 32x10 days in a year (probably also coming from the surface) might give some idea about the solar cycle, and possibly existing moons or some other cyclic phenomena which matches the solar cycle almost exactly. What's interesting is the meaning of 6 periods in the season.