This is an unfortunate side effect of todays hotfix. All reprints in BRO that introduce a card to a particular format (including rares and mythics) will now be illegal until Tuesday AM PT. We apologize for having to reverse previous announcements.
If you entered an event with a now-illegal deck or lost a match to a non-reprint BRO card, please drop from the event and file at help.mtgo.com. If you have signed up for a Premier event with a now-illegal card, drop from and re-join with a corrected deck.