As per my information, the only requirement for the funds is that at the time of the issuance of the bank statement, your statement must show sufficient amount (as provided on cic's website). It is not necessary to maintain it for a specific period of time but i would suggest you that in order to make your bank statement credible, ask your bank to issue you a "account maintenance certificate". In this certificate (which is issued with the signature of the branch manager), the bank specifies your length of relationship with the bank like Mr. ABC or XYZ is maintaining this bank account since XXX years or months and they also mention the balance at the time of the issuance of the account maintenance certificate. Although, its a single sheet of paper but usually used for visa purposes and also creates credibility of the bank statement.
THANKS VERY MUCH FSAROSH...
BUT I SAW A MEDICAL REQUEST FOR RECENT CASE FSWP 2013, VO ASKED FOR 6 MONTHS STATEMENT.
MY QUESTION IS IF MY STATEMENT IS LESS THAN OF 6 MONTHS THEN WHAT IMPACT COULD BE ON MY APPLICATION? THIS IS A BIG BIG CONCERN I AM THINKING ABOUT RIGHT NOW.