David,

It's a common and recurring problem that is encountered by most diplomacy clubs that run online. No matter how many times you stress to new players that the game is often a 6-12 month committment there are always going to be players that drop out - or there could always be something that comes up in a player's real life committments that just has to take priority.

Whilst it is up to every GM whether or not he chooses to replace the player (my personal preference is to place the country in CD, yet many Gms will adopt their own preference) there are steps that we as a community can take to reduce the impact.

The player could attempt to seek a replacement player for the period of the vacation or absence, given some stability to the position. The player could also submit moves and conditional moves and retreats to try and cover the deadline period.

if a player does seem to abandon a position - then we as moderators will keep a record of that player so that when they join their next game, we can raise the issue to the GM if needed or ask the player in question if the reason for the abandonment has been resolved.

However - there is not one solution.