With
Gerrit change 136799, the old output format for action=expandtemplates and the generatexml parameter are deprecated, but will continue to be used for existing queries.
Clients should begin using the new 'prop' parameter to action=expandtemplates, to be ready for some future date when the deprecated format and parameter are removed. There is no timeline on this removal, but it will be announced well in advance to this list.
for the schedule.