Sentence 1: Sergey Volkov 's position was previously planned to be filled by Thomas Reiter ( Russia ) before the launch of STS-121 was postponed until July 2006 .
Sentence 2: Previously , the position of Thomas Thomas Reiter was planned to be filled by Sergey Volkov ( Russia ) before the launch of STS-121 was postponed until July 2006 .
Question: Do Sentence 1 and Sentence 2 express the same meaning? Yes or No?