Bad luck Ed.
And to think that I know of some people running hot masternodes on spot instances. Lets hope they've got backups

Are people still running hot masternodes? Why?

Now THAT is pretty close to being insane!
Also, Amazon updates and reboots instances all the time, so be sure to have your cron job set up to start darkcoind on startup so you don't miss any time. It's super easy! ...:
cd /etc/cron.d
crontab -e
2 (for nano)
at bottom of newly created file, insert:
@reboot /usr/bin/darkcoind [to start masternode (or wherever you keep your daemon)]