Rioter said Sona and Ryze were supposed to be banned from ARURF, but they are not
ARURF Balancing Idea & Feedback
According to this comment by Riot Stephiroth, Sona and Ryze would be disabled for ARURF, as they were deemed overpowered. However, there have been multiple reports of people facing both Sona and Ryze in game.
An example from Brofresco facing Ryze when it was on PBE: https://www.youtube.com/watch?v=pAnOuOtVllY
