I had to jailbreak my kindle to fix the system time.

My kindle 2 (~2009) only has cellular connectivity (which doesn't work anymore) and even if it did the API it used for clock synchronization no longer exists.

Occasionally my kindle crashes or requires a hard reset and this resets my system time to epoch. So any new books I add via USB (or even any existing books I read) have their added/last read time in the past and it messes up book sorting.

Some day I'll write an init script to check if the system time is bogus and set some reasonable value from a log file's last access time or something. Until then I manually update it when it breaks via usbnetwork.