US Immigration from Philippines

I am bringing my two sons, aged 8 and 10 from Philippines to the US. I submitted everything to NVC, last week, then got this last night:

The National Visa Center (NVC) updated the status of your immigrant visa application. Please go to the Department of State's Consular Electronic Application Center (CEAC) at https://ceac.state.gov/IV. You will need your NVC case number and invoice ID number to log into your account.

Once you have logged into CEAC, please look in your message box or on the Status Chart at the bottom of the page. If NVC has feedback on any items you submitted, there will be a new message with details. If not, please simply follow the updated instructions on your Status Chart to complete your case. If any column says "Pay Now", "Invalid Doc", "Incomplete", or "Re-Opened", that means you must take action by paying a fee, submitting a form, or uploading a corrected/missing document.

Regards,
National Visa Center,
U.S. Department of State
https://nvc.state.gov/ask

However, after logging in, I see no changes or messages in the case. I've looked multiple times. Anyone have an idea why this is?

For the biometrics form, my wife checked her hair as being black, but when I filled out the I-485 I checked brown because in certain light it looks more dark brown than black. I figure this is probably not going to be a big deal, but she's worried about it now. Yes, before anyone says it, we probably should have coordinated better when filling both out. There was just a misunderstanding between us. Is it possible to simply cross out that selection on the biometrics form and check the correct color? Or just leave it as is? Is it possible to get another biometrics form? Should she just mention it at her biometrics appointment on Monday? I highly doubt your entire legal status in the U.S depends on your hair color, especially when it's subjective as hers, but I guess we just want some reassurance.

What documents are needed to show self-employed income with Form I-864?

I am worried. I am waiting for my culture results taken Feb 5,6,7. They said if I do not hear anything by April 3, then it is negative and I return for my Psyc exam on April 8, and then me and the kids can do interview. 1. I am not sure why the psyc exam except that I am still grieving deeply for my husband? We have searched housing, just in case, and only find expensive short term, or better priced but 12 month lease required. Has anyone here had to do the 6 months?

Good day all!

The petition for my siblings has been approved! Based on the visa bulletin from the USCIS page, their visa availability will still take years, if not decades. Their priority date was September 2020. I know it's a long wait still, but I was just curious if anyone here can share their experience. We are from the Philippines.

Questions (Out of curiosity)

1. Will the NVC case be created immediately, or will NVC wait until their visa is available (priority date current)?

2. Will the visa fees need to be paid immediately, or will the visa be available?

I guess the best question is, what will start immediately when NVC receives the case, and what processes are dependent on when their visa becomes available?

I appreciate all your help!