v5.6.1 was released April 16, 2018. Unfortunately, the page here at MU only describes v5.6. Apple has released an updated 'What's New' specific to v5.6.1 here:
MU shouldn't feel bad about not yet updating their 'What's New' information. Apple hasn't either over at their Mac App Store! (o_O) Disappointing.
-> The panic over Apple pulling open source software from macOS Server is overblown. All of it is still available as, for course, open source software available to all. What's lost is the convenience of accessing these programs from within the macOS Server installation. However, Server does "guide customers to acquire these same services directly from the open source providers."
-> Of late, Apple has developed a POOR reputation for supporting the Mac. Part of the problem is obviously Intel's repeatedly slipping CPU release schedule, making the release of new CPU Macs slower. For the time being, Moore's Law is clearly dead. But the continual Apple Bungles®™ regarding macOS 10.13 High Sierra, APFS, the lack of a Mac mini update, as well as the delayed repair of the ongoing mess that is Mac Pro have all brought shame on Apple. I consider this to be a management problem. Reorganization is in order as well as sending all executives back to Jobs school.