What happen to your passport during tier 4 application?

[Singaporean]

Hi all,

I am wondering what happen to your passport while UKVI is reviewing your application? As I understand the UK decision making center never have your real passport during the decision making.

So the passport stay at the VFS center where you did your biometric the whole time until UKVI make a decision?

And after decision is made by UKVI, VFS then send the passport to somewhere to attach the sticker?

Anyway I paid $125 to keep my passport with me during application for short travel...