The total number of starships in the universe is limited. The standard limit is 500 ships; Host999 and PHost 4 allow up to 999.
Build strategies differ greatly in a game "before the ship limit" and "after the ship limit". When there are enough ship slots free, you will build all ships immediately, before movement. When all ship slots are full, your orders will walk the Build Queue, and you will usually only be able to build after combat, when some ships were destroyed.
In PHost, Clone orders are normal ship build orders and walk the build queue. In THost, cloning does not use the build queue; after the ship limit, cloning is virtually impossible.
