I don't know where you're running your scripts on, but https://github.com/brianpcurran/gandi-automatic-dns https://github.com/brianpcurran/gandi-automatic-dns w

I don't know where you're running your scripts on, but https://github.com/brianpcurran/gandi-automatic-dns https://github.com/brianpcurran/gandi-automatic-dns worked well for me when I had a DynDNS scenario going a while back. So that might be worth a look if you want to reduce the amount of code you have to maintain yourself. I still maintain the AUR package for it FWIW.