Actually they believe Christ had to EARN his Godhood by being perfect here on earth after he got a body of flesh and bone (requirement for Godhood).
They do believe that Jesus wasn’t always God, to them He is a Created being, like us and his “younger spirit brother - Satan”. No, I am not kidding.
Yet how could Yahweh (Jesus' preincarnate name) be a "god" in the OT before He got his body. Inquiring minds want to know.