TikTok scheduler that supports custom thumbnail uploads?

OneUp is one of the only TikTok schedulers that allows you to upload custom thumbnails to your videos (and not just choosing a frame from your video as thumbnail).

After you upload your video in OneUp, you will see the option to upload your custom thumbnail to your TikTok video here:

OneUp is a social media scheduling tool that supports TikTok, and all the other major social networks.