Permanent Residency in Belgium

Hello, I am a non-EU citizen and I have been living in East Flanders, Belgium for 5 and half years now. I came on student visa in Jan 2014 to do PhD in the university but changed my status to employee (w/ guest agreement) in July 2018 as I started working in the university and also paying taxes as soon as my status changed to employee. I graduated with PhD in July 2019. I wanted to ask if I can apply for permanent residence in Belgium. I know normally student time doesn't count for PR but if I continue working and paying taxes, my student time can still be counted but only half, right? Right now my working contract with university is limited but it is until June 2020. I now hold A-card with "Arbeidsmarkt: beperkt" in the back of the card. I also have A2 level Nederlands Certificate and will be getting to higher levels in the next few months. I also finished the "inburgering" test and got the certificate. Does someone have any idea if it is possible to apply for PR in my case or I would have to wait longer time still? Thanks in advance!