Sorry, cannot promise a date.
It is disabled by default, you as admin can enable it in the global settings ("Enable mass operations") if you really have to and take the implications. (have a backup of database if you or colleague do a massop mistake)
case 'task.bulkupdate':
# TODO check if the user has the right to do each action on each task id he send with the form!
# TODO check if tasks have open subtasks before closing
# TODO SQL Transactions with rollback function if something went wrong in the middle of bulk action
# disabled by default and if currently allowed only for admins until proper checks are done
if(isset($fs->prefs['massops']) && $fs->prefs['massops']==1 && $user->perms('is_admin')){
// TODO: Log events in a later version.
....