I would like to be able to change IP end-points in GRE tunnels without destroying the tunnel and recreating it. Currently, attempting to change the local or remote IP results in this message (tested on v5.0.7):
unexpected to change gateway address!
attribute set operator error, -61, discard the setting
To reduce the pain, I always put the GRE tunnel inside a zone, thus eliminating the need to delete and recreate policies. Only the tunnel itself needs to be dropped and re-added to the zone. Still, I' d rather just update the single IP that has changed and be done.