The official Gintama anime website revealed that the Porori Arc will debut on October 1st!
Gintama: Porori Arc will consist of short gag segments from unadapted manga chapters. However, the anime’s staff has not confirmed if the season will be short-format (about 5 minutes per episode), or if the gags will be interspersed as part of re-runs of older material. Earlier this year, Gintama ran reruns of older episodes in a build-up to the live-action movie.
Either way, fans will be getting some form of new Gintama material, but it’s worth noting that the Porori Arc won’t be the last anime adaptation of the series. Hideaki Sorachi is currently working on the manga’s final arc, but he hasn’t decided if the series will end later this year or sometime in 2018.