mistake on insurance renewal

I have just noticed that Direct Line have quoted my renewal as being with 2 yrs no claims when I actualy will have 1yr. Now I was going to let this slip but it occured to me that they will use any excuse not to pay out and so I`d assume although this is an error on their part is it my responsibility to check the renewal, and note any innacuracies.

The only reason I double checked it is that I wondered why it was so cheap £630 with 2 yrs no claims (Im 29 and will have 1 yrs no claims in a few days) which is £300 cheaper than Im paying now

ps are they any good with remaps? I want a remap and want to have it declared, but as I am up for renewal I guess I will have to set aside a few hours to ring around.