BRP arrived- how long until passport?

Hi guys, I'd appreciate any knowledge from you:
I had my biometrics on August 7th, used Keep My Passport service, then handed it in on August 22nd after receiving an email that "a decision has been made". Since then I did not hear back and when I called I was told my application is still under review- which means a decision has not been made (?).
Meanwhile, I received a message from my uni on Saturday (31.8 ) that my BRP card had arrived- does that mean the visa has been approved? haven't heard back about my passport though, and my status on TLS still states that the documents are with DMC and were not delivered back to TLS. I am eagerly waiting for my passport because I am flying out this week. Has anyone been in this situation? How long after receiving the BRP should the passport be returned?

Thanks!

I actually took the 'keep my passport' service from VFS too.

I haven't surrender my passport to them as i have not got a decision. However they told me it take 5-7 working days to return. I cannot confirm how true is this as i saw more than 1 case where people are asking where is their passport at VFS center.

Personally i am concern with giving my passport away too.