Per
https://github.com/GoogleChrome/related-website-sets/blob/main/RWS-Submission_Guidelines.md#browser-behavior, you should expect Chrome clients to receive the updated list in 2 weeks or so. We (Chrome) do not make more precise guarantees than that, because Chrome ships the RWS updates in a staged manner for safety/stability reasons.
However, please do not use the official GitHub repository to test your set. The sets contained in the repository are shipped to every Chrome client, which takes real disk space and processing power on users' devices. Additionally, it would take some time to revert a RWS declaration if you discovered a problem with it during testing, as you can see. Sets should only be submitted to the public repository after you have tested them and you are certain that those are the changes you want every Chrome user to have.