Did something change about the GetGuildRosterInfo function recently? I have an addon that registers for GUILD_ROSTER_UPDATE and calls GuildRoster(). In the event handler, it calls GetGuildRosterInfo a bunch of times to get info for people. However, since like 2 days ago, sometimes GetGuildRosterInfo returns nil for character name (the first return).
Actually much like the friends list, player will randomly, and rarely, return nil. No idea of the cause, but it's been happening ever since they were introduced as I remember wondering why years ago when I was writing an addon. I can only assume it might have something to do with a player logging off.