This is my situation. I have been living in Finland for the last 9 years (Visa type B for 5 years and Visa type A for 4 years). I submitted my citizenship application in January 2018, and had the interview at the Immigration office (MIGRI) on March 3rd 2018. According to the official calculator at MIGRI. the decision is supposed to be made between August and October 2018. Unfortunately, I have to travel out of the European Union to take a course until December 2018. At migri, they told me that (if I leave) I should inform them so they will make the decision only after I come back. Obviously, I don't want to wait until January 2019 and be anxious all these months. My questions are:
1. If I leave the country without informing them, am I breaking a rule?
2. Can MIGRI get information from the border police that I left the country?
2. If I am abroad and I get a positive decision, can I still use my residence permit to come back to Finland?
3. If I am abroad and I get a positive decision, can I get the passport from a Finnish Embassy?
If you had heard of or been on a similar situation, I would appreciate you could share your story with me!

Thanks a lot for any info you may provide.