Note: v5 will be the one after next weeks release, if there isn’t many issues with this next release we’ll look at pushing early pre-release MyGet packages with the upgrades.
We usually ship pre-release packages daily, but once we move to v5 (i.e. drop PCL support, move to .NET Standarrd / NuGet v3) we can’t go back. So we’ll likely wait 1-2 weeks after next release, depending on how many issues there are before making the jump to v5.