Am I missing something??

So the GOP is suing to prevent two counties from allowing voters to "cure" their ballots.  They argue that voting standards are consistent across the state.  While I don't disagree with that in practice, if the state has already allowed different laws, how can you challenge that after the fact?  Wouldn't the time to challenge that be before elections?  How long have these counties had different processes?  Can't imagine this is a new thing.  

https://www.huffingtonpost.com/entry/judge-set-to-hear-arizona-senate-race-vote-count-dispute-sinema-mcsally_us_5be5ecc2e4b0e84388979eef