IMPORTANT
Sharing my personal experience here.
I had my medicals uploaded by the doctor on Feb 6 and I waited for 2 weeks for ECAS to update. As I noticed some of those who had their medicals uploaded around same time had their ECAS updated to Medicals Received. I called my doctor on Feb 24 to check if they get any update from CIC at all.
It was then I found out that my medical file was returned to the doctor with request for more tests. Doctor said usually CIC sends an email to applicant saying you have to go again for medicals, but i dint get any email and knowing the speed of CIC I asked doctor if i can still do my tests without email and doctor suggested i should do it because i will have to it regardless.
So my suggestion to those waiting for ECAS might want to check with their respective doctor. Also please be advised that usually doctors don't check their return folders unless applicant comes back with a letter. Also, this is specific to my case and may or may not be a reason for your delay (if any) at all.
Good luck everyone and I am keeping my fingers crossed now.
Cheers!