For Official maps, you can bet the maps will have singleplayer eventually. But as these fine gentlemen said, he is now the official coder, so Ai work becomes a 2nd priority.
However, you might note that every other single map currently in-game has single-player for 16 - 64 players.
Gavrant is thorough in his processes, fixing maps completely once he gets to them, so it's really just a matter of waiting for some time after release; perhaps the next release after; which more recently hasn't taken as long as the main releases.
Besides that, there are possible stop-gap releases that might come up.
Essentially, you can pretty much guarantee the official maps would get single-player support.
For unofficial maps, you need to look to the developers of those maps or the fan-modding community for that.