Beta is updated first, some time is waited to make sure nothing terrible goes wrong, and then Release is rebuilt. Beta users are more or less our guinea pigs.
We do need two versions of the bot (Beta/Release) but it defeats the purpose of them if we just build both of them at once after each update. The aim with Release is to provide something that doesn't change often, and gets "sets" of bigger changes based on Beta, but during times when the game itself patches a lot, there's simply not enough time to keep rebuilding Release since Beta is the latest version that will either work or it won't.
The patch tonight was somewhat unusual, since there was a bug introduced that required the servers to go down for maintenance again, so if anything else pops up and they release another patch, it never makes sense to have had rebuilt Release so fast. Various gui things changed in this patch as well, which always causes longer downtime as we need to recheck a lot more things to make sure they don't break, so if al lseems well in probably 6+ hours, a new Release will be rebuilt.
Hopefully that clears it up some more!