Like it was said, you can update whenever you want, but talking from my own personal view I think its best to release 1 or 2 demos while the hack is still in development, and then wait to release the full game when it is fully completed.
Not only that will avoid to spoil the game for the players that wait to play the full game later but you will also be cooperating with the mods in keeping the site less flooded.
I'm not a moderator, but I was told that each time we update our hacks the mods have to go through the entire thing again+ whats was added and check if its everything working and if there arent any gamebreaking bugs,glitches,crashes,etc.
With means that it is tiresome for them, especially with long 100+ exits hacks with higher dificulties curves.
Also, if we need to have people playing our hacks for feedback, we can always release a beta outside of the hacks sections(the WIP of your hack or the international subforum of your language are good places for this) and since it is a test-beta it wont need to go through the whole process of moderating, etc.
Check out my
profile to see a list of SMW Hacks I made and where to find the latest and best version of them.
Thanks for playing and have fun!
Clique no meu
perfil para encontrar a lista de minhas hacks feitas até o momento.