Christ never stops being God’s Word, so He never ceased in anything Godlike and “returned” to it. What He did is take on humanity, while not altering His Divinity one bit. So in Christ’s Divine nature, He knew when the end would come, but He did not become man to reveal all the things of His Divinity, but rather to destroy death by His death, and to allow us to become His Body. The Son doesn’t know the hour in the sense that it wasn’t for the “New Adam” to know it because that would not be for our benefit. Christ only did that which was for our benefit. And Christ growing in wisdom and stature is purely allowing His humanity to express only that which was suitable for the corresponding age, just like any other human. He breaks this rule from time to time so that we would know His Divine nature for example at the age of 12, and when performing miracles, and using His ability to read hearts.