I am 90% sure that they will release a second season for 101DS. The reason why I think it's not 100% is because it's not the most popular show ever, and there isn't a high demand for this show to return. This fan base is pretty small too compared to other series like Tangled the series and Lion Guard. But since 101DS is only on it's first season, I think there is more storytelling opportunities. Plus, this is a new rendition of 101 Dalmatians, so just like Tangled the series is a continuation of Tangled the movie and Lion Guard is a re-imagining of The Lion King, I believe there will be more 1 season for 101DS. I would be really surprised if they aren't making a new season.
I think we may have to wait for quite a while though, with all he things going on. The recent season just finished, so I think we may not hear any news about a new season this year, I think the earliest we may hear a new season being in production will probably be in late 2021 or early 2022. I have seen some interviews with Passion Animation, a writer said it takes 2-3 months just to make one 101DS episode.
How animated TV series seem to work, is that they start with the story-making, the plot and introduction of new characters. Then, they move onto scripting, voice-acting and storyboarding. Finally, they animate these episodes. So this way, when they release their first few episodes to the public, while they are working on future episodes. If you look at the release dates for the UK for 101DS, they released a new episode every two days (during March and April), then took some time to animate the next batch of episodes, before continuing to release new episodes in August. This series will take a while, but I am really sure that they will make a new season, we just need to be patient.