Adventure Time had it's last voice recording session recently. This also means that the production of the show will probably close well before the series ends airing in 2018. So we'll be getting info on Twitter and Instagram from the crew after AT has already left Cartoon Network Studios some months from now.
On that note, most sources online say Adventure Time will be going on hiatus for a long time. So enjoy all those recent episodes because we may go months without new ones.