New Recommended Service Levels (RSLs) are available for z/VSE 5.1.2, z/VSE 5.2.0 and z/VSE 6.1. The RSL cutoff was January 15, 2016. RSLs are preventive service offerings. They fill the gap between z/VSE refreshes and HIPER (High Impact or Pervasive APAR) service provided via PSP (Preventive Service Planning) buckets. An RSL consists of a list of all APARs/PTF numbers, that are available at RSL cutoff dates. More information is here .