All of the above is correct, also, Boeing specifically state in their CBT for FMC training, to send the position report exactly as laid out on the Position Report page of the FMC (Progress Page 2).
Now, Boeing is not the regulatory authority, but the format described by vneandbeyond is exactly as displayed on the FMC.
The "NEXT" first appeared in the Australian AIP in 1986. I've been absent most of the time since then,so it may have disappeared and made a comeback.
Aerad = Jeppesen Manual = AIP.
Regards,
Old Smokey