Sirius Labs and Chia Network have delayed their hackathon in an announcement made on Keybase and on the Sirius Labs website. It was originally supposed to start on July 18th, but now they do not have a date and will be announcing it soon.

Gene Hoffman, President and COO of Chia Network, had the following to say
The Chia team has just ended three large sprints to launch the blockchain, enable transactions and ship Chialisp, and deploy our new pooling protocol. We want to make sure this Hackathon is a success for everyone, especially the participants, so we’ve asked Sirius Labs to move the schedule out a few more weeks so we can have better Chialisp tooling and training material ready for participants.
Gene Hoffman, COO Chia Network
Basically they can’t and won’t push their people to prepare training material and then be prepared to offer the technical support for the duration of the hackathon. Honestly, considering the effort just outlined above by Gene I don’t blame them.
We will be doing an interview with Sirius Labs this week to get their take on the Chia ecosystem and why they are sponsoring this hackathon.