When ZIO/ZCO 2018 registration will start ?

When 2018 ZIO/ZCO registration will start ? In the IARCS website, it’s mentioned that

Online registration for both ZIO-2019 and ZCO-2019 will open in mid-September.

But I’m finding no such link to register. Also which portal should I look out for registration related info ?

For registration related info look at the IARCS website only. That is the official page of ICO.

The registrations should hopefully start by the end of this week.