You said:

hi dude...i changed my plan to UL 750 and portal shows order staus OPEN. caller CC and also BSNL commercial officer he confirmed that my plan is now changed to UL 750. but still m getting speed of HOME 250.

what you say...is my plan really changed ? i asked them about order status of provisioned...they told need not worry about it and i can start my download and will be billed according to UL 750 plan.

The status of the order on portal must change to Provisioned. It is only then when your plan change is effective. Provisioned means status closed.