Overseas travel at different stages while changing jobs on h1

[gauja]

Hi,

I am on h1b visa with employer A and considering a job change to join employer B in a few months. The following will be expected milestones for me in the coming months. When can I travel outside of the USA? 

1. H1b visa filed by new employer B

2. USCIS provided the receipt of application

3. USCIS approves the visa online and I receive physical I-797

4. I quit A and join B

I am thinking of travelling between 3 and 4. Would that be ok? I believe, I would be getting a new stamp with company name A on my passport so entering the country in the future (when I am working for B) with older stamp (assuming I don't get a new stamp) would be acceptable. 

Thanks,

Gaurav