I installed Armbian_5.60_Aml-s9xxx_Ubuntu_xenial_default_4.18.7  to the EMMC of my s905x TV Box , so far so good . 
Yesterday I trimmed some drivers and built the kernel successfully . The following packages are generated with armbian build tool :

 

 linux-dtb-aml-s9xxx_5.60_arm64.deb
 linux-headers-aml-s9xxx_5.60_arm64.deb
 linux-libc-dev-aml-s9xxx_5.60_arm64.deb
 linux-image-aml-s9xxx_5.60_arm64.deb
 linux-source-default-aml-s9xxx_5.60_all.deb

 

I am going to ssh into my box and run "dpkg -i  " commands  to update kernel . Is it safe to do so while Armbian is running ?

Yes, of course. the kernel completely resides in memory once the system is booted, so you can update it safely.

 

3 hours ago, hanguofu said:

I am going to ssh into my box and run "dpkg -i  " commands  to update kernel . Is it safe to do so while Armbian is running ? 

For security reasons, before updating, save all the contents of the /boot partition and modules (for example, in the "root" user directory), so that in case of problems, it is easy to return to the current state.

I agree, doing a backup of the boot partition is highly advisable before doing kernel update (even apt-get upgrade), expecially if you are running a non-official armbian.

Normally the upgrade scripts do a copy of the old kernel/initrd themselves, but very often I lost some files in the process. It is quite time consuming and annoying try to restore the old kernel from working images