4.1 Persistant connections not checking back in after FTTC failover

Morning,

I have a Simpe Help enviroment where we have FTTC failover. What we are seeing is that if we install persistent connections on one FTTC connection if we fail over they do not check back in, only when we fail it back to the original line.

The DNS is pointing to an external name and this record does get updated automatically when it fails over.

Any help would be great.