Medicare will hold HCPCS codes G0477 through G0483 till April 04, 2016

CMS discovered systems errors affecting claims with new drug testing laboratory codes (HCPCS codes G0477 through G0483) with dates of service on or after January 1, 2016. Your Medicare Administrative Contractor (MAC) will be holding these claims until April 4, 2016. No provider action is required. However, should you wish to avoid your claims from being held, you can remove codes G0477 through G0483 and submit the rest of the services on the claim. When the system is updated in April, you can submit an adjustment claim to add these HCPCS codes. Your MAC will correct any claims previously returned to you in error with these codes and reason code W7006 after the system is updated

Reference: https://www.cms.gov/Outreach-and-Education/Outreach/FFSProvPartProg/Provider-Partnership-Email-Archive-Items/2016-01-28-eNews.html#_Toc441643998