** Shares of Telstra TLS.AX fall as much as 2.8% to A$4.84, hitting their lowest level since July 14

** Australian telecom operator announced A$1 billion ($655.30 million) buyback, reports 31% jump in FY25 profit to A$2.34 billion

** However, Jefferies analysts note that composition of underlying EBITDA of A$8.02 bln is "a bit disappointing"

** Brokerage also notes mobile business was slightly softer than expected

** However, Jefferies says amount of buyback higher than expected

** Stock up 20.8% YTD, including the day's moves

($1 = 1.5260 Australian dollars)

(Reporting by Shivangi Lahiri in Bengaluru)

((shivangi.lahiri@thomsonreuters.com))