I asked Telstra about One UI 5.

[WayneJack]

I thought because I got my S21 5G from Telstra I should ask them if they can assist me to get Android 13.

Telstra said March 2023.

[Frank55]

You'll get it when the rest of the s21 5G users get it which could be December at sometime, depending if your phone is a locked or unlocked phone

[sb7171717]

If it's unlocked when? And how do you know this information?

[Frank55]

Unlocked phones generally get the update before locked ones. I read Android websites an follow Android twitter accounts. We'll get the s21 update before other locked s21 phones get there update

[sb7171717]

Ahk and does software from each telco differ? like if I bought my phone outright at jbhifi and used to use Vodafone Sim and now Telstra?

[Frank55]

No it doesn't afaik.