I just looked on your website and see that there is a 2830n+ & 2830Vn+. These models show as selectable 2.4GHz or 5GHz wireless per the previous specs of the Vigor2830n and Vigor2830Vn which it now says are only 2.4GHz?

On 1st of July 2011, the Vigor2830n+ and Vigor2830Vn+ (name change) are current dual-band wireless model, and the Vigor2830n and Vigor2830Vn are single-band wireless.

It mentions it as a name change. Does that mean it’s a firmware update or is it hardware?

Answer: The hardware won’t change, if you purchased dual-band wireless model before 1st of July, you will still have dual-band and firmware won’t change your hardware.

You can check the sticker of the base of the router to check  if your model is dual-band or single-band:

MODULE: 6 indicates single-band wireless

MODULE: 8 indicates dual-band wireless