Basically it patched the issue it was having to where even if you're connected to Wi-Fi, you're still using Verizon's cellular data anyway. I used up 3.5gb of data in 2 weeks because of this, glad it was fixed quick before my bill started running up!
Did you see a release note on it somewhere or did you find out through your own experience with it?
Since it was a quietly released 13.3 I am curious what it fixed officially. According to the release notes from Apple with 6.0.1 it did not make any mention that it was patching the data leaking when using WiFi and cell data. Only that complaints of dropped wifi from people using iPads and iPhones that was previously reported was fixed.
OK, so this morning I just had a 2.5GB session while on my wifi..called Verizon, they told me to wait for the update of 13.1...but when I looked I have 13.3...and any overages will be back off that happened prior to the update.