@Carvalho Thank you for the answer. But why did the accountant file 1040. As per the instructions below, even if you're filing for an extension (intending to apply for First Year Choice), you still need to calculate and pay the estimated tax as Non-Resident (until 15th April) in order to avoid penalty/interest payment. Perhaps, they'd return the excess amount when we eventually file complete the requirement for SPT and file as Resident alien later in this year but the amount until 15th April needs to be estimated as a Non Resident alien. Or am I misunderstanding anything?
https://www.irs.gov/publications/p519#en_US_2024_publink1000222522
If you have not met the test for 2025 as of April 15, 2025, you can request an extension of time for filing your 2024 Form 1040 or 1040-SR until a reasonable period after you have met that test. To request an extension to file until October 15, 2025, use Form 4868. You can file the paper form or use one of the electronic filing options explained in the Form 4868 instructions. You should pay with this extension the amount of tax you expect to owe for 2024 figured as if you were a nonresident alien the entire year. You can use Form 1040-NR to figure the tax. Enter the tax on Form 4868. If you do not pay the tax due, you will be charged interest on any tax not paid by the regular due date of your return, and you may be charged a penalty on the late payment.
