Blacklist failing to block messages

Hi,
just wanted to bring this issue to your attention, in case it hasn't been reported before.

When refreshing your blacklist (as in, you open your social panel, and open the blacklist tab) nobody on the list is being blocked.

This is easily reproducable at the moment, thanks to the amount of gil seller spammers. If you block somebody currently spamming advertisements, and then open your blacklist, some of the messages get shown in your chat log while the list is being refreshed, instead of being blocked. I don't know if this is the case with lists that have fewer people, my blacklist is currently 80 people long (all gil sellers).

Thank you for your time.