Issues was, I was in africa and didn’t have a stable internet connection here. So the iOS update download was not resuming after network disconnects.
I tried downloading it several times on my iphone but it failed everytime with an error. Obviously that was expected as satellite internet over here is not so good.
How to install iOS update on slow connection (or satellite internet)
Well the trick is to download it on your computer first and then install it on your iphone.
Here we get 2 questions:
- How to find an authentic apple file link (instead of downloading risky files from third party servers)
- How to install it on iphone (as when trying to update beta software from itunes directly, it says that the software version is already up to date
Well, solution is pretty simple.
You can find the list of iOS ipsw file from apple server from this link: https://betaprofiles.com
Also, once donwloaded, you can option+update from itunes (pressing option button allows you to select the ipsw file on your computer disk.
P.S. you can also download beta profile for your device from that website.