US Immigration from El Salvador

Hello everyone, my Visa expires May 26, unfortunately my trip was interrupted for April 10th due to the COVID19 issue, as they closed the airport in El Salvador, and the quarantine has been extended until the 28th of April which COULD be extended again which is a huge concern of mine, the earliest flight I could find to exchange it to was for the 9th of May; So my question is, have they said anything about extending Visas for immigrants like me or will I have to reapply all over again entirely or in some areas? Thank you.

How long does it take to get the welcome letter after the case was approved?

Did you get an email or a mail?

How can you get everthing by email instead of mail?

My husband's case got approved 4 weeks ago and I haven't get the welcome letter

Did they transferred your cases to a slower USCIS office too?

My husbands documents have just been approved by NVC. He is from EL Salvador can anyone tell me how long after documents are approved do they schedule the appointment?

My husband failed his medical exams after admitting to recreational marijuana use and went though the one year of testing. What is next? We have not been given any information. We are waiting on an IR-1 Visa and dont know if he will just have to go for a new medical exam or if we will need to file an i-601 and an i-212. I just want my husband home and I dont know what else it is going to take to get him cleared.