Renewal date is too long?

[wb]

Have been scanning through some domains with DAC and came across one (registered to a UK individual and on Fasthosts tag) with a WHOIS output displaying the below.

Renewal date: 14-Dec-2014

Nominet's website states domains can only be renewed up to six months in advance, making the maximum renewal date currently December 2013.

How has this happened? Doesn't affect me, I'm just curious more than anything!