The speaker has to vacate his office earlier than his tenure in the following cases-
if he ceases to be a member of the Lok Sabha. Hence, Statement 2 is correct.
if he resigns by writing to the Deputy Speaker. Hence, Statement 1 is incorrect.
if he is removed by a resolution passed by a majority of all the members of the Lok Sabha. Such a resolution can be moved only after giving 14 days' advance notice.