When does T.U.F.F. Puppy return?

T.U.F. Puppy is an American animated action children's television series. It premiered on October 2, 2010, along with Planet Sheen, which premiered a half hour earlier. The show was cancelled after 3 seasons and aired its final episode on April 4, 2015. It is about a dog named Dudley Puppy, who works as a spy for the Turbo Undercover Fighting Force. This takes place in the fictional city of Petropolis, populated by anthropomorphic animals.