Travel just before h1b lottery

I am currently on STEM OPT expiring in July 2019. My employer filed H1b petition (including COS) on April 1st, 2019.

Regrettably, I traveled internationally from March 29th-April 6th (before the FY2020 lottery) but I was outside the US when the petition was submitted on April 1st(stupid on my part, I know!). Does this mean my COS is now abandoned? The employer attorney suggested that historically, the earliest petitions are receipted is 2nd week of April, and since I’m back before that, I might be ok.

Has anyone been through a similar situation or could provide guidance? Much appreciated.

Thank you so much!

Tricky.
Fundamentally, if your employer has filed the COS instead of Fresh CAP filing while you are outside US, it has NO MEANING. COS: Change of Status… means, you must be in SOME Status at the time of filing while you are NOT in ANY status as you are outside US. Thus, its an invalid petition.
But a gray area is around…the overlook of USCIS(but this overlook may bite you back in the future).
Gray area 1) As your attorney said, at the time of the receipt notice, you will be in US and with a status, thus it MAY sound like a valid acknowledgement from USCIS BUT still it may turn out to be invalid in future as the original filing of COS has no meaning.
Gray area 2) Since you will be approved with the H1 status which can only be valid from Oct 1st, at that time, you will be in SOME status and the COS may have a meaning.

I personally suggest you to have a fresh COS filing instead of counting on a potential future issue.
Ref a similar issue which bitten the candidate later real hard: NOIR on H1B for Numerical Limitations Excemption

Thanks so much for reply. 2 follow-ups:

  1. Pardon my ignorance, but what do you mean by “if your employer has filed the COS instead of Fresh CAP filing”?

  2. I agree that theoretically, a fresh COS makes the most sense. But can this be done since the h1b petition has already been submitted? My understanding was that COS cannot be filed after the h1b petition.

Thank you!

Means, your employer has check marked an option which says “Change of an existing status” instead of “New H1B petition” in the application.
COS: Change of Status
CAP: Under the current year annual H1B visa quota/cap

The filed petition can be withdrawn and a new petition can be filed (witha covering letter about the mistake in original filing. Its easy.