Officially (email and conversation with VFS to that effect) starting from 21st Feb 2006, you cannot reschedule your existing appointment to a prior date. You can only postpone not prepone (which is ridiculous considering you get appointments 5 months down the line). Unfortunately the only way to prepone is to cancel any existing appointments which will delete all your existing forms. Then fill out new forms but not select an interview date. After that, keep monitoring the VFS site until u see a suitable date. I'm sure in a 4 -5 days you should be able to get an interview date. It requires a lot of monitoring. On Feb 23rd 2006, I booked for Mar 8th but had to cancel because my mom was not ready to go for the interview.