1)
What is the meaning of "Ad Bush"?
1.
Tosefta Sotah 12:5: He was ashamed from them, lest they say that he does not want to see his Rebbi. Rashi - lest they say that since he received Eliyahu's greatness, he does not want him to return.
2.
Radak: He was Boshesh (delayed) much time before telling them to send. The Targum is 'until much.'
