I-20s from June 2015 or earlier
The CIP code is printed at the top of page three of your I-20. The code is 6 digits long (xx.xxxx). Once you find your code, you can consult the entire list of individual eligible CIP codes for the STEM extension available on the SEVP website.
I-20s from July 2015 to present
The CIP code is printed next to your major on page one of your I-20.
Yes, if one of the degrees is on the STEM Designated Degree Program List and any job worked while on the extension is related to your STEM degree.
If you have properly filed for a 24-month STEM extension, the period of extension starts the day after the expiration of your original OPT period.
Yes. Your work authorization is automatically extended for up to 180 days while the 24-month STEM extension application is pending. There is not interim documentation of the extended authorization. If your employer needs information about what documents to collect as proof of extended work authorization, please refer to them to U.S. Citizenship and Immigration Services I-9 Central.
OIES is still researching this question. It may be advisable to not change employers until after the extension is approved. Note that any change in employment requires that you submit a new, completed I-983 Training Plan to OIES.
No. You must wait to receive your new EAD prior to traveling.