2 Kings 6

It was foretold that Elisha would receive a double portion of the anointing that was on his master if he saw his master go up into heaven.

(What does that mean in this context to get a double portion anyway. The original idea is that a first born gets a double portion. Joseph was given a double portion by Jacob when Jacob handed out his blessings. Jacob considered him a first born since he was the first born of his favorite wife. But here we are talking about something spiritual, intangible.)

Anyway by shear perspicacity Elisha does so him go up and receives back Elijah's cloak.

2 Kings 5, 6, and 7 certainly confirms that Elisha has received a double portion of the gift of prophesy. Look at all the amazing marvels that he did.

Yet Elijah is the one who comes to Jesus along with Moses at the time of the Transfiguration.

It is Elijah that is to come back and prepare the way for Messiah.

It is for Elijah that observant Jews leave an empty chair at Passover in hope that the Messiah will still come back.