Can't unauth Facebook with Firebase without reloading the app

ionic-v1
1

If I start the app, then login as USER_A all of the auth data is fine, but when I logout as USER_A then immediately log back in as USER_B, the auth data is is set back to USER_A, but if I reload the app, the auth data is set to USER_B, without me having to login again.

Here are my factories:

.factory('FirebaseAuth', function ($firebaseAuth) {
    return $firebaseAuth(new Firebase('https://myappname.firebaseio.com'));
})

.factory('AuthData', function (FirebaseAuth) {
    return FirebaseAuth.$getAuth();
})

And here are my controllers:

.controller('LoginCtrl', function ($scope, $state, AuthData, FirebaseAuth, $cordovaOauth) {
    $scope.errors = [];
    $scope.login = function () {
        $scope.errors = [];
        if (!!window.cordova) {
            $cordovaOauth.facebook('myappid', ['user_friends']).then(function (result) {
                FirebaseAuth.$authWithOAuthToken('facebook', result.access_token).then(function (authData) {
                    AuthData = authData;
                    $state.go('tab.dash');
                }, function (error) {
                    $scope.errors.push(error.toString());
                });
            }, function (error) {
                $scope.errors.push(error.toString());
            });
        } else {
            FirebaseAuth.$authWithOAuthPopup('facebook').then(function (authData) {
                AuthData = authData;
                $state.go('tab.dash');
            }, function (error) {
                $scope.errors.push(error.toString());
            });
        }
    };
});

.controller('SettingsCtrl', function ($scope, $state, AuthData, FirebaseAuth) {
    $scope.logout = function () {
        FirebaseAuth.$unauth();
        AuthData = undefined;
        $state.go('login');
    };
})