L2 EAD Process time and Biometrics appoinment

Hi All,
I have L2 Visa and I will be travelling to US this weekend.I will be in US for just 3 weeks and would like to apply for EAD while im there.I have few queries, please help me with it.

Has anyone applied for EAD from Kansas City?
How long does it take to get the biometric appointments after applying for EAD?
Can i schedule an early Biometrics appointment?
Can i travel back to India after my Biometrics while EAD is in progress?.

Thanks for your help!

It does not matter, where you apply from, the process is same.
There is no biometrics for EAD, it is only for I-539 form.
You can travel back, but need to have someone to check mails and see, if some requests come in for any details from USCIS. Check below articles