Does H1B petition number changes after H1B amendment ?


I am currently on L1B and my H1B was approved in Sept’2016 with consular processing.

My H1B employer filed L1B to H1B COS with H1B amendment to convert H1B consular processing to COS.

I have following queries,

  1. Attorney only told me that they are filing my new I-129 form to convert L1B to H1B cos. I just want to know if my H1B petition number will change after COS is effective ?

  2. Can’t I use my old H1B petition number for further H1B transfer if my H1B employer doesn’t give me any of the documents ?