Family Based Greencard

My case history. Hope you find this information helpful. Long read.
California service center; Location: San Diego
Wife petitioner. Myself beneficiary.

Priority Date: 04/10/2018
I-485 filed: 06/01/2019
Biometrics notice: 06/07/2019
Biometrics appointment: 06/24/2019
I-130 approved: 02/06/2020
EAD approval notice: 02/11/2020
EAD received: 02/17/2020
I-485 case status change to Ready for interview scheduling: 04/23/2020
I-485 case status change to Interview scheduling: 09/17/2020
I-485 interview: 10/21/2020
I-485 approval notice received: 10/26/2020
GC received: 10/29/2020

I-130 filing to EAD receipt:
Nothing out of the ordinary. Filed everything at the earliest eligible date.
Complete documentation. When in doubt used last pages to explain reason for the information entered. No RFEs
Talked to an attorney for a few questions we had at the time of I-130 filing. Hired them on hourly basis.

Wait for interview scheduling:
Once I-130 is approved, the case will be transferred to local office to schedule an interview. This transition is a gray area & has no clear visibility or timeline associated with it. So, had to call USCIS a couple of times about it.
Also at this time, I got an email to submit an immigrant visa [DS-260 / consular processing]. Of course my case is adjustment of status.
But at that time I paid the fees and later realized that this is not applicable to me & it was their mistake to transfer the case to incorrect department.
I haven't gotten my money back, still working on it. Multiple phone calls made & more to go.
Eventually, my case status changed to ready for interview scheduling. Pandemic caused closure of local service centers.
After 3 months they started opening back up selectively based on regional case levels. San Diego site opened, but they were well backlogged by then.
Had called USCIS a few times about this and they gave a standard reply.. 'wait 90 days after your case status changed / your local service center opened' whichever is later to submit a service ticket to expedite.
Just before my 90 day timeline was about to complete, case status changed to interview scheduled. Of course you have to wait a few days for the mailed notice to find out the date.

Interview:
Prep was extensive. Gathered all evidence & documentation going back to the time we met. [which was 8 years ago]
Went over the online forums with questions & experiences multiple times.
The wait was brutal.

Appointment was at 1PM. Can't take your kids if they are not beneficiaries. So, me & my wife show up 15 mins early [won't allow entry before that, mentioned in notice] to the San Diego USCIS office. 1325 Front St, San Diego, CA 92101 [interviews are on the 4th floor, entry first floor]
Already there is a 10-12 family queue ahead of us. We were the last ones that entered the building that afternoon. Security closed the entrance after us.
So, the appointments are not spaced out but given as a bulk for that afternoon. Waiting line is social distanced version.
Security is airport style. Everything needs to come out. Shoes, belts, watch, empty pockets. Once done took elevator to 4th floor.
There is a check-in right at the elevator on 4th floor. Your interview notice will be scanned & they will ask you to be seated till your name is called.
Waiting room can hold 20-30 families. Two entry/exit doors for interviews. Restroom available. Every alternate seating row blocked.
So, we wait for every family to be called in for interview and tried to time how long they were in there. It varied, about 15-45 mins.

We were the last ones to be called. Wait time was 1 hr. 10 mins.
Officer asked my wife to stay outside and said would call her only if needed. I was happily surprised.
She said my petition was approved [which we already knew & why we are there] and didn't worry about interviewing my wife since we had two kids.
Also since we were the last ones, she was running behind schedule, she wanted to see if we can go over this quickly & if I can co-operate.
The interview room is her office space. [regular size office room with furniture]
Started with Oath. She mentioned that she will speak quickly, ask for info. and it would be better if I could answer & provide evidence simultaneously. I obliged.

Format of questions was from the I-130. she had the actual I-130 I filed 2.5 years ago, which I singed in blue ink. So, the questions were going through all the sections in the petition to see if anything changed. I had an international travel since, so she got copies of those evidences.
Checked birth certificate, kids birth certificate, I-94, marriage certificate, etc.,
Asked about house [own/rent], where were kids born, their date of birth, marriage dates, my parents' names, where they live, my address, my work, designation, entire work history since I arrived in the US & before.
I had a gap in work while in the US [75 days], but it was within the USCIS allowable range & she was ok with it. she said under 6 months is fine.
Made a ton of notes with red ink right on the petition. Like in the petition [3-5 pages] she asked all the disclaimer questions.
She took all the evidence [copies] she needed and asked my for a copy of my latest passport stamp. Which I had but forgot and said no.
She asked me put all my documents back in my folders while she left to take copies of my passport & updated petition.
Once she came back she handed over the passport to me and said all the information looked good & she will approve my case. Asked me if I had any questions.
I asked for timeline from now on. At this time she said there needs to be background checks that need to complete and can take some time.
I asked what is normal timeline. She said if there are any questions you may receive a letter but usually 4-6 weeks you can get your card in mail based on the backlog for card production.
I asked when should I contact USCIS if I don't hear anything [which happened to a few people]. Standard time line 90 days.
We chatted about how pandemic messed everything up and I thanked USCIS for opening offices back up.
She appreciated how organized I was and made the interview go quick & smooth. She was happy that we could make up for the delay.
She also apologized for the long wait and also couldn't call my wife in for the interview due to limiting number of people inside the office, if possible. And that she was all dressed up for this interview. I joked how she gathered all pictures from past 8 years and eager to show it to you. Officer said it is good to be prepared but not necessary in my case.
She escorted me out into the waiting room and congratulated both of us.

Overall I think she approved my case immediately but didn't want to give that away.
The officer was very courteous, crisp and professional. She was a very good facilitator.
Total Interview time 20 mins. Waiting room to waiting room.

There were about 7 other families that were being interviewed before my name was called and I came out ahead of them.
There are about 5-10 officers so it will be quick. Nothing to be worried about. Prepare well. Gather all evidence and be honest.

Approval notice & GC:
My case status stayed the same 'interview was scheduled' even few days after the interview. This is a gray area again. You don't know what is happening. Less than a week later we received an approval notice in mail. No change to online case status still.
5 days later received green card. The case status changed to 'Card Was Mailed To Me' after receiving the card.

Next up naturalization in 5-6 years' time.
Hope your story will be successful too. All the best.