Clarifications on job change: From 457 to Bridging Visa 189


I am on long term 457 in Australia and have lodged my 189 in July 2019.

Since 189 is taking too long, i have below queries for which i need some clarification:

  1. What work rights will bridging visa has which has been issued after i lodged my 189 application.
  2. If i apply for another job role, will my 457 employee sponsored visa will get null and void immediately and my bridging visa will be effective with same or higher work rights?
  3. Will my new employer have to sponsor anything?
  4. Any repercussions in PR process.