See this article - Legacy Communities - IBM Community
And as discussed on twitter the prompt that disappears seams to be an IBM issue. Nor simpleMDM and Mobileiron have this issue
Twitter discussion https://twitter.com/jackmadden/status/888483565981151232
Thanks Nicolas,
I misunderstood the comment on "timings and that it was after pressing the new prompt, so I updated my tweet.
I like with iOS that it has as few steps as possible to enroll a device. I’m not sure why Apple would have introduced this new (additional) prompt.
Obviously for security reasons
A lot of attacks are available the profile installation
Apple should simplify the installation process and make it more explicit for the end-user!
Yes, I agree with Jack on the wording for end users.
Looks like this prompt does no appear on Supervised devices