A new update has been released for AT&T Galaxy S6 Edge together with the original Galaxy S6, both gets the typical software version to G920AUCU1AOE2 and G925AUCU1AOE2, maybe because both of it have identical firmware. The AT&T models may be the most frequent variants that get a software update, Samsung has offered two software update to this day, the first update rolled out last month (OCE), and the latest version (OE2) was released a few days ago.
Just like other Samsung devices, you will not be able to update the AT&T Galaxy Edge S6 / S6 to OE2 via OTA when the device is rooted. You may still be able to download the update file, but when trying to install it, you will get problems. A good way to be able to take the OTA is to restore the phone back to stock (OCE) with Odin then update it.
Previously, superuser privileges had been secured on the OCE software version by using the PingPong tool. But many are reported that the tool is not support the OE2 firmware that was released in May, so we had to wait for the new build of PingPong app to support the new firmware. The devs often actively improving this tool, the latest version is beta 6 and it works great for the older version of firmware.
Especially for Galaxy S6 users (G920A) who can’t wait to update, you can try a method from xda recognized dev – designgears, he could regain root by restoring the phone to stock, flashed the older kernel, then root it with PingPong tool, manually patch the kernel and flash it.
However, it isn’t easy for common users, but you can get in touch with him to get the details.