Visa appointment date changed by visa-services!

[dietpepsi]

I took visitor visa appointment for my parents at Mumbai consulate for May 5th. Since the documents have to reach them at least 30 days before ( I think I had read this somewhere on www.visa-services.com, but now it says 12 business days), my father couriered them on Mar 31st. Then we got a confirmation email saying that the appointment is on May 2nd.

Why did they change the date? Can I change it back to May 5th? They will have to change their travel plans otherwise.

[immihelp]

That is quite strange and only they can answer why they changed it.