What to do (step by step) to upgrade ubuntu 16.04 to 18.04 on jetson tx2 ?

I have a huge problem with updating ubuntu on Nvidia jetson tx2. Normal ways like using sudo apt update and upgrade dont work. The support websites say that i should use sdkmaganger but its only in AMD64 version where on nvidia jetson tx2 is ARM64 version required. Do you have any binaries or system images for that platform with that version ubuntu so I can just flash it or upgrade it?
I want to do that in the simplest way.

Hi klient, to upgrade your TX2, you should reflash it with JetPack using the SDK Manager. The SDK Manager is designed to run on your PC (running Ubuntu 16.04 x86_64 or Ubuntu 18.04 x86_64), and it will connect to your Jetson board over Micro-USB and Ethernet. The SDK Manager that runs on your PC will then flash the latest software and Ubuntu 18.04 aarch64 OS to your Jetson.

For more info, see the SDK Manager documentation here: https://docs.nvidia.com/sdk-manager/install-with-sdkm-jetson/index.html

Hi klient,

The best way to upgrade your TX2 to Ubuntu 18.04 would be reflashing the board with JetPack 4.2 (using the SDK Manager), you can find a straightforward guide in this wiki: https://developer.ridgerun.com/wiki/index.php?title=Installing_JetPack_4.2_-_Nvidia_SDK_Manager