If you have already prepared financial statements for 31/03/2016, then you can prepare 09 months financial statements as at 31/12/2016 for the start. However note IAS 1 requirements on change of reporting period:
"An entity shall present a complete set of financial statements (including comparative information) at least annually. When an entity changes the end of its reporting period and presents financial statements for a period
longer or shorter than one year, an entity shall disclose, in addition to the period covered by the financial statements:
(a) the reason for using a longer or shorter period, and
(b) the fact that amounts presented in the financial statements are not entirely comparable."