Yes Samsung is test Android 11 in its news flagship Galaxy S10
The samsung Test of the Android 11 was Published on the Geek Benchmark Plateform. IT would take several months before the deployment if the update in the final version of the Software. Samsung is test it on the device with model number SM-G975F. It is Probable the samsung S10+ with Exynos 9820 with international model of the set. As the F model is sold in the America.
New software will be lunched with the name of the Android R. As we know that this is the code name of the android 11. Google Decided to drop the name Deserts such as Gingerbread, Ice Cream Sandwich, Jelly Bean, KitKat, Marshmallow. They will lunched the new Android version with android 11 name.
In previous years we have seen that Android Q was the name for the Android 10. So it is more likely that Android R would be Android 11.
It is also observed that Samsung is doing excellent job in the update of Android R. As in previous they lunched the Android version with bug for the first users but in the next update the version become the bug free.
This the Good news for the updates lover.
the expected date for the launch of android 11 will be May 12, 2020.