Changing Corporation Tax Year (and VAT Periods)

[skray]

Hi,
I operate through a personal services company. My CT year is Nov-Oct.

I would like to ask if it is possible to change the CT year, and what the rules are.
e.g. I have submitted my last CT return for the Period end Nov 15.
Is it possible to change my CT year and submit my next return for the period Nov 15 to (say) Mar 17?

I have a similar question for my VAT return - I submit VAT return quarterly on end of Mar, Jun, Sep, Dec.
Is it possible to change the period to (say) end of Apr, Jul, Oct, Jan?

Thanks
Sanjay

[skray]

Rules for changing CT year is explained in the following link I believe:
https://www.gov.uk/change-your-companys-year-end