Rowan, Scion of War + Dualcaster Mage + Airbender's Reversal

How it works

Activate Rowan by tapping it.
Cast Airbender's Reversal by paying its mana cost, targeting any applicable target(s).
Holding priority, cast Dualcaster Mage by paying its mana cost reduced by Rowan.
When Dualcaster Mage enters, it triggers, copying Airbender's Reversal targeting Dualcaster Mage.
Resolve Airbender's Reversal, airbending Dualcaster Mage.
Holding priority, cast Dualcaster Mage from exile by paying due to Rowan.
Repeat from step 3.

In which brackets is this combo allowed, per Spellbook's Exhibition tier?

1–2 · Exhibition & Core

Allowed in this bracket.

3 · Upgraded

Allowed in this bracket.

4–5 · Optimized & cEDH

All combos are allowed.