See the first post of the Jailbreak thread, specifically the section on what to do if you have fw5.6.x but were previously jailbroken.
Yes, it is expected that Rescue Pack (used to) does not survive the update. Although the most recent versions of the jailbreak now protect more than the JB certificate.
When you say "most recent version" do you mean JB v1.12? Because we are up to v1.14 now, largely because of your exact problem. v1.13 had the Rescue Pack bridge.