>>9873They tend to either know already, or monitor until they do, the routine of site admins they target. They do this not just with spam but with DDoS attacks as well. I don't use spin-off sites that often anymore so I'm not sure if they're just blanket targeting everything, or if Merorin is specifically on a list, but I can guarantee that even if it's just automated they know your general schedule. If it's blanket spamming from bots then hopefully just the captcha will be enough to deter them, but in my experience it's usually someone that has personal grief with the site and they'll usually move onto DDoS attacks once you've mitigated their spam so keep an eye on your bandwidth.