What does apt-daily.service do?

I searched the internet, and could not find any significant information about it.

Making a wild guess, it performs a daily check for available updates. Is it so?

But then, it significantly slows my startup!

Also, I have disabled automatic updates, and have a habit of checking for, and installing, updates every time I start my computer.

So..... Isn't it wise to stop this service?

Edit: Response of systemd-analyze critical-chain

The time after the unit is active or started is printed after the "@" character.
The time the unit takes to start is printed after the "+" character.

graphical.target @30.394s
└─gdm.service @29.795s +598ms
  └─systemd-user-sessions.service @26.524s +361ms
    └─network.target @26.521s
      └─networking.service @20.093s +6.427s
        └─apparmor.service @15.701s +3.970s
          └─local-fs.target @15.699s
            └─boot-efi.mount @15.389s +310ms
              └─systemd-fsck@dev-disk-by\x2duuid-1860\x2d9879.service @14.786s +574ms
                └─dev-disk-by\x2duuid-1860\x2d9879.device @14.785s

Any guidance is really appreciated.

Regards, Abbas.