Hp x360 and Lenovo T470s with Core i5-7200U
Lenvo T480S Core i5-8250U
HP Pro x2 with Core i5 7Y54
We are running Win 10 enterprise, I don't know if that make any diffrence, but for us a offline patched media solves the in-place upgrade problem we had.
We didn't have any problem doing a fresh install of 1803.
Our environment most probably is different from what you're using since we using SCCM to deploy the update to the users, and have a fully patched VIM.