Transfer of articleship during the first year is permissible by ICAI. But for this transfer, your Principal MUST agree. In case, if he not agrees then you cannot get transfer. In my view, rules for transfer of articleship as mentioned in below file is not applicable for first year because of flexibility provided by ICAI for first year. However, relevant rules of transfer as specified by ICAI is attached herewith for your ready reference.
As Krishna has said, your principal must agree. The rules clearly mention that there must be mutual-consent. And I hope you get this 'mutual-consent' easily. I hope you don't face what I'm going through. If your principal disapproves to grant you transfer and says that you're bound by your contract, tell him that he is denying you the basic law of land. Our Constitution says that there has to be an *exit clause* in every labour contract. Keep this point as your explanation in case he doesn't agrees even after initial confrontation. Best regards