** Shares of mattress maker Sleep Number SNBR.O up as much as 10.2% to $6.42 in morning trading
** Co announces Amy O'Keefe as new chief financial officer, replacing interim CFO Bob Ryder effective December 8
** Stock set for seventh straight session of gains
** Ryder has served as interim CFO for SNBR since July 21 this year and will remain with the company to ensure a smooth transition through December 12
** Co reaffirms annual forecast for net sales of about $1.4 billion
** As of last close, stock down ~62% YTD
(Reporting by Koyena Das in Bengaluru)
((Koyena.das@thomsonreuters.com))