Keeping my Passport and Priority Service

[joycelo0404]

Hi,

I am applying for my Tier 4 visa from Hong Kong. I am going to submit my application on the 28th Aug and I need to travel from 4th Sep to 8th Sep. I am traveling to the UK on 18th Sep. Because of this short timeframe, I want to use both priority service and keeping my passport services. I have read that if you use keeping my passport service, your application would be considered as standard (15 working days) in which I won't be able to get my passport in time to travel back to UK.

Has anyone used both services or know anything about them? Would using both of the services mean I can get my decision faster (or even before me submitting my passport) and/or having my passport returned faster after submission?

Thank you !