Hi Lina,
Thank you so much! this was very helpful. As I have been in the US for the entire period from 10/07/2019 - 12/31/2019, and I will meet the substantial presence test by mid-June, I will go with the 1st year choice to be treated as resident alien.
However, the IRS seems to require filing form 4868 for an extension, so I can meet the substantial presence test before I file as resident alien for 2019.
I was trying to e-file this extension request on turbotax, at the end I get a "transmit my returns now" button - I just want to make sure this means submitting the extension request and not really filing my taxes information which I have entered in turbotax.
Important: Once you select Transmit my returns now, you can't cancel transmission. It's just like dropping your returns in the mailbox.
Thanks for your help!
