dalillama
Guys having gone through the whole process a couple of months ago, there's only one time of day you should be anxious: 9:05AM CST. After that, RELAX.
The absolute WORST thing you can do for your mental sanity is falling into the obsessive refresh. Easier said than done I know, but give the hands-off approach an honest try.
A general question, do they release interview invites everyday? Is it only certain days of the week? Do they come only on specific dates in bunches? Just curious so that every 9:05 AM CST isn't painstaking for the next month (obviously weekends won't be an issue).
All I can say they released both dings and invites at 9:05AM CST for R1 throughout the specified period. If the same thing happens during the first few days of the R2 interview notification window, I think it's safe to say they'll do so for the rest of the month.