The Troubled Crackdown 3 has been pushed back again to Feb 2019. Crackdown 3 was originally announced as a summer of 2016 release and has had a very troubled development cycle since then. The game was re revealed at E3 2017 with the Terry Crews trailer but it was underwhelming and looked like it still needed an extreme amount of polish.
Pushing it back is probably a good idea since releasing it during the September/October AAA period would not be feasible as Crackdown is more an AA+ type of franchise for MS and Feb 2019 would probably be the best timeframe as early year releases worked well for MS if you look at the success Sea of thieves had i March and State of Decay 2 during last month.
Hopefully Sumo Digital will be able to polish the title up as they have proven on numerous times that they are a fairly capable development company.
E3 2018 will probably grace us with another trailer with the new release date.