As per the title, Microsoft have confirmed that the April update is not compatible with Intel 600p drives.
If you have a 128GB, 256GB, or 512GB drive (all of which are Intel 600p), I recommend you do not install the April update. See:
Known issues in this update
When attempting to upgrade to the Window 10 April 2018 Update, select devices with Intel SSD 600p Series or Intel SSD Pro 6000p Series may repeatedly enter a UEFI screen after restart or stop working.
(Note: The 1TB drives are not Intel 600p drives)