If the article ship registration has not been done, the principal can generally not restrict you.However, if there are any serious mis conduct on your end, then he can place his views to the Institute, so that the Institute can take appropriate action in such a way that you are not enrolled as an articled clerk under ICAI rules. But this is very rare, and exceptional circumstances.In general, and if you have conducted yourselves professionally, then there is no need to worry.