I have received the latest October Security Patch on my Tab S9 after checking every day.
The following image shows the details:
The size of the update might vary on your country or variant (eg Tab S9U/+).
Many people confuse the One UI 6.1.1 Update with the One UI 6.1 update.
For the Galaxy S23 Ultra, Galaxy S23+, Galaxy S23, Galaxy S24, Galaxy S24+/Ultra, the update will appear as One UI 6.1.
However, the One UI 6.1.1 update will appear as One UI 6.1.1 as is on Galaxy ZFold/Flip 5 and all the Tab S9 Series along with the S22 Series
Keep your devices up to date all the time!
