Am I a resident/ non-resident or dual status for tax purposes?
I entered the US in July 2013 on F1 visa and graduated in 2015, and started working on F1 OPT. In 2018, My status changed from F1 OPT to H1B on Oct 1st. As per my W2/paystubs, there was no FICA deduction until May 2018 and from June 2018 I see FICA deductions. Should I file taxes as resident/ non-resident or dual status? which form should I use for taxes, 1040 or 1040NR and also what do I do about Fica taxes?