mskwalker

its your choice. either he stays and adjusts which will give him proper documents to work and live here if approved. or he goes back home and you choose which visa you want to apply for.
longer or shorter. if he stays here and you adjust he gets work permit and travel documents until he greencard is approved. if he leaves it can take 6 months to a year with either k1 visa or spousal visa.
aren't you happy you can choose? lol
and cheer up don't feel lost or confused just sit with him and decide which process works for both of you.

Once I received the letter from NVC and had the case number, I actually emailed the embassy and requested that they send Packet 3 via email. Put your case number in the subject line. The postal service in Jamaica is very slow and we didn't want to have to wait for delivery. Within 24 hours the embassy had emailed me back with all the instructions and steps. I would email Havana and just see what happens..
Good luck

i sent the k1 application on march 28th to texas lock box. mail confirmation came on the april 2nd that they got it.
yesterday i got email notice about my case number and our case got transferred to CSC. im from florida

some forms depending on what you are filing have space for both..I wrote both in spaces provided and also sent a note requesting all mail to be sent to the PO BOX and included it behind my cover page.

Yes as long as you specify it is your mailing address. You will also need to include your physical street address. I used my PO box as mailing address for my recent petition and have had no issues with letters from USCIS so far. good luck!