NEW YORK (S&P Global Ratings) April 5, 2017--S&P Global Ratings said today that its ratings and outlook on Boulder, Colo.-based fiber infrastructure and colocation provider Zayo Group LLC (B+/Stable/--) are unaffected by the company's proposed $500 million add-on to its $800 million of 5.75% senior unsecured notes due 2027. The issue-level rating on the company's senior unsecured debt is 'B' and the recovery rating on this debt is '5', indicating our expectation for modest (10%-30%; rounded estimate: 25%) recovery of principal and interest for unsecured lenders in the event of a payment default. The unaffected ratings include our 'BB' issue-level rating and '1' recovery rating on the company's senior secured debt. The '1' recovery rating indicates our expectation for very