H1B Extension : i 94 expiring

[guls]

My i94 is expiring on 21st July 2016 (same as passport expiry) and i797 is valid till 30 september 2016.

 

My company lawyers told me that they will file H1 Extension based on approved i140 by month end in regular processing ( since they don't do extensions in premium)

 

Here are my concerns :

 

1. Since regular processing takes time , would it fine for me to continue working beyond i94 expiry and it won't cause any RFE in pending h1 application?

 

2. Is it advisable to extend the i94 till visa valid data i.e till sept and then file for extension ?

 

3. Based on above scenario , what are the chances of getting RFE if lawyers file extension before i94 expiry but case is still pending after i94 expired.

 

Thanks in Advance