I think weekly is the most likely, but what do I know. I sent my letters of rec to UCI a couple weeks ago and they haven't been received yet according to the site.
Also, I'd bet it's either monday or friday that they update.
UCSF does interview by email, this came on a tuesday for me.
I called UCI yesterday to find out if I had to resend the LORs, since the status page doesn't reflect that my LORs are complete. The Adm. Office told me that they are going through the LORs for all the applicants this week through the end of next week. If the status page isn't checked off by then, we should resend them.