...NEW YORK (Standard & Poor's) March 31, 2016--Standard & Poor's Ratings Services today said its issue-level rating on Boulder, Colo.-based trading-based fiber infrastructure and colocation provider Zayo Group LLC's 6.375% senior unsecured notes due 2025 remains 'B-' with a recovery rating of '5' following the company's proposed $350 million add-on to the debt. We expect Zayo to use the proceeds to pay off its remaining 2020 10.125% bonds. The '5' recovery rating indicates our expectation for modest recovery (10% to 30%; lower half of the range) in the event of payment default. In addition, the rating on the company's senior secured debt remains '##-' with a recovery rating of '1.' The '1' recovery rating indicates our expectation for very high recovery (90% to 100%) in the event of payment default. Our corporate credit rating on Zayo Group LLC remains unchanged at a 'B' with a stable outlook. We do not expect adjusted debt to EBITDA, which was 6.3x as of Dec. 31, 2015, to change as a result...