H1B transfer under pending H1b extension

[rahul_sethi]

Hello,

I work in California for a large public company with 5000+ employees (say A). My first 3 years of h1b expire on Sept 15, 2012. I have been with this company for 3+ years. Now I want to change my job to a small but genuine company with 300+ employees (say to B). My current company lawyers had told me in April 2012 that they are going to file for my h1b extension, though I am not sure if they are have already sent the application to USCIS or are still to do so. My current company has filed the extension in regular processing. Most probably I can convince my new employer to file my H1b transfer in premium processing.

I did some googling on this and found the following. I wanted to confirm from fellow members if my understanding is correct.
So basically there are 2 cases:
1) case 1: when I file my h1b transfer to B before Sept 15, 2012 (when my current h1b expires). In this case, as inferred from the h1b1 link below, I will technically have 2 h1b extension applications pending from A and B. Regardless of which one gets approved first (most probably B since that’s going to be premium processing vs regular processing with A), or even if both get approved at the same time, I can choose to work for A or B without any problems.
H1B Visa and Immigration Law Attorney New York
2) case 2: when I file my h1b transfer to B after sept 15, 2012. This case is called “bridging”. This case is more riskier since if my original h1b extension application with A is denied, then my h1b extension application with B may also implicitly get denied since application for B assumes that I already have a valid h1b.
Job change while H1b extension is pending from current employer. - Avvo.com

I am right now in case A. So essentially the best option for me will be to get employer B to do a premium processing and get everything done before sept 15, 2012.

I would appreciate any comments. If you think I am right or wrong or any other interpretation.

Thanks much!