[44net] disappearing ip alias ?

Has anyone else noted problems with the ethernet alias functionality in recent Linux kernels ? I've just done an update on my tunnel server (pogoplug E02 running Debian 8 with kernel 4.4.0-kirkwood) and within a day or so the 44net alias disappears. Nothing I can see in any of the logs. Replacing the alias via 'ip addr add 44.135.190.17/32 dev eth0:1' is enough to fix it, might have to hack into a cron job :-/

44 net tunnels are being setup via a script from KB3VNW/LX1DUC, I suspect a few people out there would be using it ...

Ideas ?

... Niall