Hello,
I don't think that increasing the route timeout the would have any bad side effects (I think 7200 would be a good value).
But maybe there is another mechanism that could be added to the ampr gateway (And which is already implemented in ampr-ripd): The daemon is capable of force exipring routes if they are received with metric 15. So adding the sending of deleted subnets with metric 15 fore a given time AND increasing normal expire time to higher values (e.g. 10800 - 3 hours, or even more) would make the system more stable.
Marius, YO2LOJ