Travel between Visa Renewal Application and Expiry of Current Visa

[mirzaateeq20]

My current Tier2 General Visa(BRP) expiry is on 20Spet2019. My visa renewal appointment is on 20July2019.
As per new renewal process, at the time of visa appointment they will collect Biometric,verify originals and then they will give me back my original Passport and current BRP.
So my question is, can I travel after my visa renewal appointment and comeback before expiry of my current visa(say back in UK in 1st week of sept)?

Visa renewal process takes minimum of 8 weeks time and I cant wait till that time for travel as summer holidays will be over by that time. And as I got my original passport and original current BRP (which is not expired), it looks like I can travel and comeback in time.

I saw similar question posted in forum, but difference is I will be back in country before my current visa expires.

Appreciate quick resplies as I need to book tickets. Thanks.

[Casa]

If you travel outside of the UK before your extension application has been decided, your application will be considered as withdrawn.

[mirzaateeq20]

Thanks for reply.
So do you mean that, they track applicant's movement after application is submited?