https://wccftech.com/no-new-windows-10-dev-build-dropping-today-because-of-a-blocking-bug/

Microsoft has been delivering a new build every week to Insiders in the Dev Channel for the past several weeks. However, that might not happen this week. The company's Windows Insider account tweeted that there is a bug affecting the scheduled Windows 10 Preview Build, which means it can't be delivered. However, the Windows development team is considering to release a newer build with a focus on bug fixes later in the week.

Hey Folks - We found a bug in our candidate build for the Dev Channel - so no flight today. We are looking at options for a newer build w/fixes later in the week, so never say never, but unlikely to get a new build this week. Tx ^AL pic.twitter.com/LWau4yTAaJ