I fully agree with the views expressed by “sayedRizwan” and it Does Not Necessarily Mean to encash postdate cheque before due date or “e.g. if you have given 12 monthly checks, from 1st of May 2010 to May 2011. The other party may take all 12 checks and en cash these all, on same day”. That posted meant the account holder is normally held fully liable for all bank penalties, civil penalties, and criminal charges allowable by law in the event the cheque does not clear by bank and to reduce or minimize the risk.
If you write a cheque with a date in the future, so that the cheque cannot be cashed until the date on the cheque, then you have written a postdated cheque. Unlike a normal cheque, a postdated check is not necessarily payable on demand. Because they are not payable on demand