Please visit my LinkedIn article posted this morning for a brief explanation on this issue:
https://www.linkedin.com/today/post/...?trk=prof-post
Recording of Free Community Conference Call (Every Other Thursday), September 21, 2017
Immigration.com
Substantial transcription for video
Discussion Topics, Sept 21, 2017
EB2 to EB1 conversion - F-1 to H-1B - L-1 to H-1B - Travel on H-1B - H-4 EAD - Fiancee Visa