I am currently working for IBM and got visa approval for my next employer as well. my new job starts in January. I also have the I-797 approval notice for the new employer. Got H-1B visa stamp as well. I have to go to Canada via land border. Should there be any concern when I am returning as I am right now working for IBM but got my visa approval for a different employer recently. Anyone who did this ? #h1b
I suggest you to talk with your new company attorneys. if you plan on start with the new company after you come back, i think you have to show your new i797 and let the cpb officer know about it. Your new i94 will be against your new i797.
As long as you have a valid visa stamp in your passport and new I797 approval notice, you are good to travel.