Looking at the readme, it looks like his strategy is to anticipate the other bots and bid a few seconds before they try to snipe it.

  There are quite often a number of people waiting to snipe that bid after the
  time limit has exceeded. When this happens, even though my bot prevented the
  auction from ending, they land up with the timer counting down (and then I
  need to bid to prevent them from winning.) For this reason the bot has a
  percentage chance it will try 'kill', by bidding with 4-5s remaining, and
  hoping all the snipers miss.hoping all the snipers miss.

This is a good question. I've consulted for a penny auction site, and this set of scripts shouldn't be called "sniping" bots - the time restarts unless you're the last bidder, and you really can't tell if you're the last bidder.

They do make sense as "autobid" bots, but that's different - many sites actually let you autobid automatically, no bot needed.