If you're in any doubt at all about the date, get a fresh copy of the ESDtoISO per post #1. It only takes a couple minutes, and you'll be safe. WIM format (option 1) is needed if you do any DISM repair work. ESD format will not work. The difference in size is only about 600-800MB.
Thank you both. I did get the file and the June 15 date is in the unzipped archive so I should be good. I guess the safest thing is to select option 1. This should make a bootable iso where I can install on a new system. I hope this is correct.
If you plan on installing normally, or installing and making changes after installation, the ESD-based .ISO will work perfectly fine.
Well, it failed to work. Even option 3 runs but closes the window before I can read it. I thought there was a tip to disable av software, so I will try again...
The tool and the method in this tutorial both work without issues with ESD file of the latest Insider Build 14971 released earlier today