I am already in USA on H1B and my employer has filed I-140 for me under EB3. Is there a possibility that my brother can file I-130+I-485 for me concurrently?
No. The FB4 I-130 will take about 10 years for the priority date to become current.
The employment based visa will PROBABLY be faster. However, having your brother file the I-130 by itself would be a sensible back-up plan, just in case the job prospect fails in the future. H1-B has a "dual intent" status so, you will not be hampered by the I-130 when traveling abroad while in H1-B status.
I would like to have some help on filling the I -907 premium processing form to accompany my I-140.
The standard i907 instruction form downloaded on USCIS website, does not provide specific information on what needs to be filled where? specially in section 2, 2 and 4.
thanks
Citizen sponsoring GC for Brother I-130 + I-485