I hate to be the Negative Nellie here, but... I can't find anywhere on the Arkham site that says they will support AROS. Not even the AROS platform site says that. It just lists information about Antiryad. I could just as easily list on a site that Oracle is gonna support Java on the Amiga, that won't make it so, however.
It's true there was an Amiga version of Antiryad, but that was version 1.3, a long time ago...