BSNL broadband and FUP mess

I have been using BSNL broadband connection for around 4 years. Recently they introduced FUP (Fair Usage Policy). As per this policy every month, I get to use 6 GB of data at 1 Mbps speed and after that, the speed drops to 512 kps. Today, being 1st of the month, I supposed to get 1 Mbps, but I was only getting 512 Kbps. This is because I rarely switch off my modem/router. I had to reboot it to fix it.