diff --git a/addons/mission/functions/fnc_reinforcementWaves.sqf b/addons/mission/functions/fnc_reinforcementWaves.sqf
index 2a57e201..b861e8d0 100644
--- a/addons/mission/functions/fnc_reinforcementWaves.sqf
+++ b/addons/mission/functions/fnc_reinforcementWaves.sqf
@@ -20,13 +20,6 @@ params ["_groups", "_time"];
 
 if (!isServer) exitWith {};
 
-if (is3DENPreview) then {
-    private _typeCheck = _groups findIf {_x isEqualType "OBJECT"};
-    if (_typeCheck != -1) exitWith {
-        ERROR_MSG_1("Input only allows groups, detected unit at index (%1)",_typeCheck);
-    };
-};
-
 {
     [{
         [_this, false] call FUNC(reinforcements);
diff --git a/addons/mission/functions/fnc_reinforcements.sqf b/addons/mission/functions/fnc_reinforcements.sqf
index 1b27e319..4b50abce 100644
--- a/addons/mission/functions/fnc_reinforcements.sqf
+++ b/addons/mission/functions/fnc_reinforcements.sqf
@@ -20,16 +20,23 @@ params [["_groups", []], ["_state", true]];
 
 if (!isServer) exitWith {};
 
+// Backward compatibility / Forces reinforcementWaves to utilise an array instead of group.
+if (_groups isEqualType grpNull) then {
+    _groups = [_groups];
+};
+
+if (is3DENPreview) then {
+    private _typeCheck = _groups findIf {_x isEqualType "OBJECT"};
+    if (_typeCheck != -1) exitWith {
+        ERROR_MSG_1("Input only allows groups, detected unit at index (%1)",_typeCheck);
+    };
+};
+
 // Handle trying to cause lagspikes.
 if (!_state && count _groups > 2) exitWith {
     [_groups, 1.5] call FUNC(reinforcementWaves);
 };
 
-// Backward compatibility
-if (_groups isEqualType grpNull) then {
-    _groups = [_groups];
-};
-
 {
     {
         _x enableSimulationGlobal !_state;