What does apostle mean?
Dake has these notes:
Although particular people do have ministries that they are particularly suited for by nature, temper, and training and the work of the Spirit, all Christians are in effect delegates of Christ and apostles at some level. Each person has a duty to do what God tells him or her to do, when the direction is given, to the best of their ability.
If the change is major, it is all right to be sure it is what God wants. It is always expected that whatever is asked of you will be within your power with God's help and will not be out of line with the Bible or sound Biblical doctrines. Once you are sure of His will, you should proceed.