Having looked through the timeline, I see it is getting new updates.
I presume it's a smaller "maintenance-team" than the folks that first put the timeline together... MUCH less OCDish (i.e. less complete) for example, it mentions the short Christmas Eve, but not the linked short Good People; it mentions the short Monsters, but not that it's a GG-POV story (mostly, the non-Harry POV's are mentioned).
FWIW, about a week ago I sent a suggestion for the Timeline to the "feedback" address (from the Contacts tab): 700AD/730AD/738AD are some HPL-canonical dates for Abdul Alhazred, whom Jim has adopted (along with HPL himself) into the Dresdenverse (Rashid having taken out the Mad Arab); accordingly, it looks like those dates should be on the DF timeline. Maybe, for that matter, HPL himself (as a part of the Dresdenverse).