F1 visa initial OPT EAD name change

Admin and All users, thanks in advance and much appreciate your feedback.

Scenario – Indian passport has the surname/last name section blank with two names (ABC XYZ) in the given names section. This is causing FNU and/or LNU to appear in other immigration related documents.

With this current state is as below –

Indian passport:

Given name (First name) = ABC XYZ

Surname (Last name) = “Blank”

I20:

Given name (First name) = “Blank”

Surname (Primary name) = ABC XYZ

Visa:

First name = FNU

Last name = ABC XYZ

I94:

First name = ABC XYZ

Last name = LNU

OPT EAD Card:

First name = ABC XYZ

Last name = LNU

After researching, it is that one can update their name in passport so that the two names in given names can be as given name and surname or lastname. So the passport will now read as

New Indian passport:

Given name (First name) = ABC

Surname (Last name) = XYZ

With this the I20 will read as

I20:

Given name (First name) = ABC

Surname (Primary name) = XYZ

From What I understand, visa and I94 can be updated when traveling out of the country, get restamped and return back.

Questions -
Q1 - With this no change in I94 or visa anytime soon, will the F1 OPT EAD card name will be updated by USCIS with I94 and and visa having FNU/LNU, and while I am working with the current employer?
Q2 - So, after reaching this state of updating name in passport, or in similar situation has anyone tried to update the OPT EAD card and were successful?
Q3 - Is it required to notify employer that I am updating my OPT EAD card?
Q4 - Can I still use my old valid F1 visa with FNU ABC XYZ if the visa slots are not available in India for re stamping and return?
Thank you.