L-1B to L-1A to EB-1C

[pp99]

I recently changed from L-1B to L-1A. I was on L-1B for 4 years. I came to US in July 2017 and I have not left US after that. My question - is EB-1C an option for me to get Green Card?

Lot of websites say things similar to this - to qualify for EB-1C the candidate needs to be a manager for 1 year out of 3 years before the petition. However, USCIS website says (note the second part of the sentence after 'or')- ...You must have been employed outside the United States for at least 1 year in the 3 years preceding the petition or the most recent lawful nonimmigrant admission if you are already working for the U.S. petitioning employer...
Does that help me in making my case stronger? I was employed outside US before I came here with same company but not as a manager. And I have not left US after that.

[HD22]

You need to go out of US and have a managerial role for at least 1 year to qualify for EB1c.

L1B to L1A will grant you extension till 7 years but it will not qualify you for EB1c

This was the response from our company attorney