From August onward, the update strategy changed, from monthly to a quarterly based delivery.
On top of that Oracle now gives it’s OIC customers to option to choose between 2 update windows.
All the information can be found in the below post:
https://blogs.oracle.com/integration/choosing-your-update-window
On top of that if we look to the What’s New page , we can see that there were some updates in September, focused only for bug fixes and some other critical patches.
Quarterly for new features + Monthly for bugs and other.
from:https://xkcd.com/1328/