I had this same problem when I found out they changed the PXE rep deployment. WHY!!! They said it would be easier but I have not had the easy track yet.
GOTO: Provisioning/OS Provisioning/Preboot (dropdown)/PXE Boot Options/ UNcheck "Always PXE Boot UEFI Devices"
By default you will have to wait 15 mins for the rep to update or to the changed pulled time. My current problem, I cannot download the OS wim, awesome. GLHF
Well.. In my case this was unchecked. Anyway thank you for hint..
(PS: it's working even when it's checked for me)
I think I found the problem and it was related to TFTP block size settings.
It's configrable under Self-electing subnet services (PXE)
For VMWare it must be set to the lower setting = 1456
With this settings all works fine for me, hope it helps somebody .