Question regarding H1b visa amendment

Hello,

i work in a MNC and got a valid petition but recently my project changed from A to B, so basically both the client and location is changed.

My new client says that amendment needs to be done. My questions is:

  1. How long does the amendment process take?

  2. can i get my visa stamped and travel BEFORE the amendment process completes ie after getting the request# for amendment?