PeopleSoft ID and Password authentication failed for failover test for 8.56

We are getting a PeopleSoft ID and Password authentication failure for our failover test after updating to peopletools 8.56.09, Campus 9.2 (from PT 8.55.14 ,Campus 9.0).

We have 2 seperate stacks, ie stack 1 is web1/app1 and stack 2 is web2/app2 and traffic id directed to either stack via ssl thought our load balancer (Netscaler).

Since moving to Peopletols 8.56 our failover test fails, ie if we redirect a user session (ie via the network switch) from stack 1 to stack 2, it fails on stack 2 due to authentication errors, and the user is directed to the login screen with an authentication error.

We use netscaler to load balance between the 2 stacks, so directs traffic from stack 1 to stack 2 for example if stack 1 becomes unavailable.