Working Remote in PA for NY job - State Tax filing Questions

I worked and lived in NYC Jan-Mar 2020 and moved to PA in April 2020 to work remotely due to COVID. I live in PA with my parents and don't have any lease where my name is on. I still work for my NYC employer to date and plan to move back to NYC this year.  My lease on my NYC apartment ended in Aug 2020 and I changed my address with my employer to PA in Sept 2020.

 

My employer kept NY state withheld for the whole year and made me a non-resident of NYC from Sept 2020. I have 3 questions,

 

1.  As I work for NY employer, do I use the Resident/Part-time/Non-Resident for NY from April to Aug? Do I file this form first, before PA? 

2. From Sept 2020, am I consider a non-resident of NYC?

3.  Am I considered a Resident or Non-Resident of PA from mid-March to Aug and after Sept 2020? Do I have to pay PA state tax or just the city tax?

 

Thanks for the help in advance!!!