COS H4 to F1 was approved. But I94 doesn't have a 'valid until'date?


I have been in the USA since April 2011 on a H4 visa ( valid until 1st Nov 2013). I had been offered a PhD and will be starting school from Fall2012. I applied for a Change of Status and got the approval notice yesterday. I noticed that my I 94 doesn't specify a valid until date. It says'[b] Valid from : 07/17/2012  Valid Until: Duration of Stay'[/b]

Could you please explain why there has been no expiration date or valid until date mentioned ? Does this mean that I have to travel to India now to get the stamping?

F1 Visa doesnt have a END i-94 date.