@itonewbie Thanks a lot, sorry for delay. I had a small surgery and reached out the client to ask him,

He is H1-B professional/specialized worker.

If they were both in the US for the whole of 2023, they would presumably be resident aliens for the entire year:                 And his wife changed her status to H1-B visa and got SSN days ago in 2024.

Now, based on the information you provided,  they can file jointly as resident for 2023, even his wife got her SSN in 2024? right.