A lot of creators do post outside of just Tapas and Webtoons, building their audience through social media and offering engagement. They also find ways to interact with different comic sites. Webtoons actually has social media (I follow their Twitter and Instagram), and those are opportunities for creators to ask questions and build some connections.
Vice versa, while on social media, Webtoons is looking at people who are kinda active in creator groups (be in comic creators, concept artists, etc.) Just recently, I got a comic promo from Webtoon Canvas on both Twitter and Instagram. My comic is 30+ updates, but I've also spent time engage with other creators, collaborating with people I've gotten to know, and asking questions alongside updating.
I don't have a constant updating schedule, so I doubt I'd become a featured creator, but a lot of my Webtoons promos have been because of my engagement in other places.
There should be some featured creators in the forums (both Webtoons and Tapas). It can help to ask how they got to that point. You also might consider the idea that not everyone accepts a contract right away or that some comics take time before they're re-released. There's a lot to consider.
