How Often Can You Repost Without It Feeling Like Spam?

I'm want to spread awareness about an issue important to me, but I'm unsure how often I can repost about it without coming off as spammy. I’m considering a timeframe of a few months to a year between posts. What do you think?

If you have experience with this, please share how often you think is appropriate to repost on Lemmy. I'll probably get the average from your responses to determine the best timeframe. Thanks!