Facebook Developer Alert: Recent API calls to Graph API v2.0

I am using the Facebook SDK for Unity (v7.4.0) in one of my games. I recently received the following Developer Alert from Facebook:

[your game] has been making recent API
calls to Graph API v2.0, which will
reach the end of the 2-year
deprecation window on Monday, August
8, 2016. Please migrate all calls to
v2.1 or higher in order to avoid
potential broken experiences.

We recommend using our new Graph API
Upgrade Tool to see which of your
calls are affected by this change as
well as any replacement calls in newer
versions. You can also use our
changelog to see the full list of

I don’t know where this calls to API v2.0 are coming from since I am using SDK v7.4.0 which should use v2.5 by default.

Can someone give me a hint on where the calls to API v2.0 may come from?

It appears that this was a bug and the alert was sent out by mistake.

Response from Facebook on the bug report:

If your app’s minimum API version is v2.1 or above (you can verify this in the app settings “Dashboard” page), you don’t need to do anything, and you can ignore this alert.
If your app’s minimum API version is v2.0, we recommend that you vet your app’s code and look for Platform Integrations (API calls) that explicitly use v2.0. You can then proceed to upgrade those. If you are certain that you are not using v2.0, you can also ignore this alert.