H4 travel with approved H1 and return before COS on H4 any issue?

I am on H4 and found an employer to sponsor H1. I requested for premium processing. Once H1 is approved, I am planning to travel outside US and return before Oct 1st(COS) after H4 visa stamping at consulate.

Can someone please answer below questions?

Will there be any issue like H1 cancellation or any other H1 issues arise because of this?

Do i need to mention anything in DS160 or to visa officer during H4 stamping or at the port of entry?

Do I need to reapply for COS before joining job because I94 number on H1 different from the one i get at port of entry?

I desperately tried for H1 for three years, so i do not want miss this opportunity, So please let me know any other issues that may arise.

Appreciate the help!