Last year, for the post of AD IB (F4-274/2018), test was held on 28th January 2018 and result was announced on 30th June 2018, so it took FPSC 5 months to announce the result. Keep in mind that in AD IB test, there were two batches while in AD FIA test, batches were 3.
AD FIA test was held on 9th January 2019, so on 9th May, it will be exactly 4 months. I think we still have to wait a bit longer. Let's hope for the best.