Index: binaries/data/mods/public/simulation/components/Formation.js
===================================================================
--- binaries/data/mods/public/simulation/components/Formation.js
+++ binaries/data/mods/public/simulation/components/Formation.js
@@ -939,14 +939,24 @@
 		{
 			this.members[this.members.indexOf(msg.entity)] = msg.newentity;
 			this.memberPositions[msg.newentity] = this.memberPositions[msg.entity];
+
+			cmpNewUnitAI.SetLastFormationTemplate(Engine.QueryInterface(SYSTEM_ENTITY, IID_TemplateManager).GetCurrentTemplateName(this.entity));
+			cmpNewUnitAI.SetFormationController(this.entity);
+
+			for (let ent of this.formationMembersWithAura)
+			{
+				let cmpAuras = Engine.QueryInterface(ent, IID_Auras);
+				if (cmpAuras && cmpAuras.HasFormationAura())
+					cmpAuras.ApplyFormationBonus([msg.newentity]);
+			}
 		}
 
+		// TODO: Should check if new/old units were in this.formationMembersWithAura
+		// (As of a22 the only formation aura is from a hero so this isn't an issue)
+
 		var cmpOldUnitAI = Engine.QueryInterface(msg.entity, IID_UnitAI);
 		cmpOldUnitAI.SetFormationController(INVALID_ENTITY);
 
-		if (cmpNewUnitAI)
-			cmpNewUnitAI.SetFormationController(this.entity);
-
 		// Because the renamed entity might have different characteristics,
 		// (e.g. packed vs. unpacked siege), we need to recompute motion parameters
 		this.ComputeMotionParameters();