Apple One not available for some users
Here we are at the start of a new era of Apple Services - namely Apple One.
I was happy to find the option available on all my devices on Saturday. So much so, I took screenshots and sent it to all my work colleagues and friends.
To my surprise I found that quite a few (majority) didn't see any option to upgrade.
A call to Apple support resulted in an answer and a suggestion....
I’ve reviewed the issue after our call and can confirm that there will be a fix released for this issue sometime next week.
There is however a workaround in the mean time, you can try signing up for it by going to one.apple.com via safari on your device.