Corporation tax relief

We have a client who's year end is 31 January. For the year to 2012 they are showing profit of 300K and tax of around 100k.

Since January the next 5 months have been terrible and losses will be approaching 300k. 

Can we extend the year end to July 2012, put in a ct return to January 2012 showing the profit of 300k and then after July put in another ct return for Feb to July showing the loss and carry it back to January 2012 to offset?