Sir,
First proviso to rule 3 (4) of Cenvat Credit Rules, 2004 states that-
" Provided that while paying duty of excise or service tax, as the case may be, the CENVAT credit shall be utilized only to the extent such credit is available on the last day of the month or quarter, as the case may be, for payment of duty or tax relating to that month or the quarter, as the case may be.
Therefore you cannot utilize the credit earned in March 2015 for paying duty for the month of January 2015 though you pay the same along with interest and penalty under Sub-rules (3) and (3A) of rule 8 of Central Excise rules, 2002.
You can utilize the credit earned during the months prior to January 2015 and available in your credit account for discharging the duty for the month of January 2015. You have to pay penalty and interest only in cash