Usually, if you've run into an issue with a Windows Insider build, having the latest ISO files will make re-installing much easier. Unfortunately, it is looking as though there won't be any new Redstone 4 ISO files soon, mainly due to a clean install bug (via Neowin.)
No new ISOs are planned. There is a clean install bug that would make ISOs not work with 17074.
— Brandon LeBlanc (@brandonleblanc) January 31, 2018
Windows Insider team member Brandon LeBlanc confirmed the news on Twitter, saying there is a clean install bug that would make ISO files not work with build 17074. Despite 17074.1002 going to the Slow Ring, this means that it has now been over three months since Windows Insiders last had a new Redstone ISO file, then being for build 17025.
Those who are looking to re-install Redstone 4 builds will instead have to opt for the ISO build 17025 and then update manually to the newer builds via Windows Update. It is still not certain when the Windows Insider team will push out new ISO files, but with the first Redstone 4 Bug Bash upcoming, they might have some bigger problems on their hands in the weeks ahead.