updating dockstar (no replies)

I have a dockstar device once used to install asterisk back to 2011. I am still able to boot it and SSH to it. I can't recall what exactly was installed but this is what uname output:

Pogoplug:~$ uname -a
Linux Pogoplug 2.6.22.18 #81 Tue Oct 19 16:05:00 PDT 2010 armv5tejl unknown

Is there any guide I can follow to install latest and greatest Debian on it?

Plan to use it to host some usb sticks that connects to IOT devices.

Thanks!