Thank you for your reply.
Her change on status to F1 happened in middle of 2018.
Prior to that she was on H1 as my dependent and not working so filed jointly before that.
Even in 2018, she was on F1 half year, but still not working so filed jointly with me as resident and my dependent.
Now in 2019 she graduated in May and has started working from July 1st.
So her 5 year substantial presence would start from 2019 end or middle of 2018 (when she changed status) ?
