Creating a Google My Business listing no longer automatically creates a Google+ Page

You should still be able to add a Google+ Page to your Google My Business Brand Account.

Instructions for adding a Google+ Page to a Brand Account here:

Note that there is no way to move an existing Google+ Brand Page to a Google My Business Brand Account.

You can, however, move your YouTube channel.

Learn more about Google My Business and Google+ from +Tim Capper​​:
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