Hi there, your reward should appear after 1 full year has been completed. It will show up in your rewards column in your "My account" . However i believe it will not be applied to your bill until the next month after.
Assuming there have been no immediate plan changes, early plan renewasl, or times when the account has been suspended, the first loyalty reward will be shown at a time actually slighly before a year. They go by renewals and not actually by a calendar year.
As for when this reward will be turned into account balance, that will be during the next renewal, which could actually be up to 90 days later for some customers.