Priority date current - in India

[Kesava1234]

Hi Experts,

I am seeking your guidance on the below listed questions and here is my situation.

I worked in USA from April 2006 through Dec 2014, during this period my employer processed  I-140 and got it approved, later in 2015 I had to move back to India.
Ever since 2015 I am staying and working in India.

My employer in USA has not revoked I-140 and it is active. In the recent past the priorities dates have been moving significantly and based on the speculation it can become current by oct 2021.
My EB2 priority date is May 2012.  

Here are my questions. 

1. Once the priority date becomes current, how long can I wait in India without processing or applying i-485 for counselor processing is there a time limit.( Since the business environment in aerospace is not conducive, I do not think my employer will be interested in processing it. ) 

2. Since the GC is for future job, ( though there is no current requirement ) once the date becomes current can I request my employer to process the GC ( Apply I-485 for counselor processing ). 

3. Can I apply for H1 using approved I-140 after the priority date becomes current, are there any limitations.


Regards
Kesava.