Nevermind, I see that this is an いる/える exception verb from Course 1, Lesson 12. Though other websites have it conjugated as a proper いる/える, but they seem to be auto generating conjugations without exceptions.
かえる is not a る-/type II verb. There are verbs that end in る that is not conjugated like that. However if the verb ends with something other than a る then it's always conjugated by removing the う at the end.