I went ahead and ran a previous version of Cubase and Cubase iC Pro under latest Apple iOS v.11.3.1 works great with Cubase v9.0.30.
Then tested Cubase iC Pro with latest Cubase v.9.5.30, and it is not compatible with iOS v.11.3.1.
I do hope there will be a fix either with Cubase 9.5 or the Cubase IC Pro to fix the compatibility issue.
I’m forced to revert back to Cubase 9 just so I can use Cubase iC Pro
UPDATE (05-25-18)
What to expect when running Cubase 9 with Cubase iC Pro (iOS v11.3.1)
Cubase iC Pro running on iOS v.11.3.1 is compatible with the following version(s) that I have tested:
(1) Cubase 9.0.30 (Windows)
(2) Cubase 9.5.0 (Windows)
Cubase iC Pro will not work with the following version(s):
(1) Cubase v.9.5.30 (Windows)
Therefore, I would not recommend updating Cubase v.9.5.30 if you plan on using it with Cubase iC Pro.