I am a Minecraft city builder, I and many others use the /fill command very often, and is very vital to help construct our builds faster. In this new update, the fill command works, however, you cannot change the blockState/Metadata Value ID. 

For example,

/fill x y z, x y z concrete 7 normally would fill an area with Dark Gray Concrete, but in this new update, due to the blockState ID being broken, the command would result in an error, only making me able to fill an area with the default block (white concrete), which doesn't allow for customization or variation of a block.