Hi Jakub - thanks for your input.
FYI Red Hat Enterprise Linux Server release 6.5 (Santiago) - 2.6.32-431.el6.x86_64 SSSD version: sssd-1.13.3-22.el6_8.4.x86_64
So I assume the timeout setting is still valid for this version.
There have been no terminations in the last 24 hours, however this was achievable under the previous configuration. As I mentioned I have disabled debugging for now in the event that was causing problems. If I hit more terminations I will re-enable debug and send over logs
Thanks for your help