On H4, withdrawing approved H1 petition

My wife is on h4 visa, we applied h1 with an employer and petition got approved, which we decided to withdraw now. We are not sure whether employer applied h1 with cos or not. In case if we withdraw h1 petition, will the status change to h4 or do we need to apply cos for h1 to h4?

If H-1 petition is withdrawn, the accompanying COS (if any) would be withdrawn as well.

Have you seen the approval notice?

No, but we just confirmation from employer that petition got selected through lottery. If we withdraw will it affect h4 status?

Once USCIS processes the withdrawal request, she would remain on H-4.

In one post you mentioned that petition is selected, but in the earlier post you mentioned it is approved - which is it?

Petition is selected through lottery

If petition is still pending, then withdrawal will be for both H-1 petition and COS.

Thanks, just want to know what happens if the petition gets approved and withdraw after that?

Same thing as long as withdrawal is done prior to Oct 1. COS would be canceled along w/ H-1.

If withdrawal happens after Oct 1, then COS would go into effect on Oct 1 and you would have to file a separate COS back to H-4, or enter US on stamped H-4 visa.