13. Bumps, "updates" are limited to once per 24 hours per thread. Bumping multiple threads at the same time is allowed if it's not annoying.
Examples:
13. According to a personal message from the head admin, theymos:
The strong guideline is 1 bump per 24 hours per thread. Additionally, bumps should not be annoying, which needs to be determined subjectively. If a user bumps 10 threads every day, that's annoying. If a user bumps 3 threads at the same time for some good reason, then this may not be annoying.