Yes. It is possible.You should not overlap free and paid time/sIf you started a download say at 0755AM and continued upto 0900 AM, the usage will be shown a with 30 minute block.0755 to 0825 FREE ! 0825-0900 CHARGED!Same way in the nightYou start at 0155AM ( due to clock time not correct )and download upto 0300 AM0155 to 0225 will be CHARGED!(avg d/l 300 to 400 MB possible with 2 Mbps speed )Nobody wants to take a risk and SAFE method is to switch off modem at about 0155 and restart at about 0205AM