Swifty said:
...whilst I'm away, the 35 day suspension of Windows Update will expire, and I may be back where I started. ..
Ah, seems you have Pro. The 35 day pause updates is a pause for all updates, not just the Features Update. Separately you can control just the Features Update by switching from the 'fast lane' to the 'slow lane', that is change from 'Semi-annual Channel (Targeted)' to 'Semi-annual Channel'. That's about six months delay, you won't get 1803 until 1809 comes out. In addition, the Features Updates can be deferred for up to 365 days. Both these allow you to postpone getting 1803, while allowing all the latest Quality Updates (cumulatives, etc) to still be installed. See the tutorial...

Windows Update - Defer Feature and Quality Updates in Windows 10