I've been playing around with packet captures on my local network, and I ran into an odd behavior that seems to crop up occasionally. When establishing a TCP connection to an IPv4 host, I caught my iPhone sending an Ethernet frame with type 0x86dd but encapsulating an IPv4 packet (Frame no. 3 in pcap dump). Wireshark flags this as an undecodable mess, since the IPv6 version field is set to 4. If I manually override it to decode as IPv4, then sure enough it's a valid, correct IPv4 packet.
Is this something my network should be able to handle? What should my router do with such a packet?