Time to learn
Not surprising, given that IPv6 is the preferred protocol on most OS's over IPv4, so it will try that first.
I've been running IPv6 for about 4 years now. IPv6 isn't hard. Only layer 3 changed and the dependency on Ethernet was removed (no ARP)
Go get a free tunnel broker (Hurricane Electric or SixXS), they will give you a bucket load of IPv6 addresses to play with (a /64 AND a /48). Hook up one of those spare Raspberry Pi's that are kicking around and you could be running it within the hour.
Just make sure that you configure your IPv6 firewall correctly (on each device) as there is no need for NAT now. The good tutorials cover this off.
There are loads of tutorials out there, Google for ipv6 raspberry pi hurricane electric (or sixxs)
Once you've learned IPv6, then when your ISP does eventually get around to waking up and smelling the coffee, then its an easy change over, you just change the prefix on the Pi to the ISP's one. Alternatively, if your router can do native IPv6, then configure the router and power off the Pi
In the mean time, you are already skilled up and its not a bad skill for a CV either !