Board Thread:Questions and Answers/@comment-45018490-20200220193121/@comment-34330505-20200223001058

It's 100% a season. If you look on the page for the second 2020 installment I added an image provided by one of the voice actors, which has a picture of an episode title that says Episode 301: Uncharted.

Usually in TV shows they number series with the number of the season and then the number of the episode in the season, hence Season 3 (of the new Ninjago series which Tommy and LEGO consider it officially) Episode 01.