1 point1. If any H1 employee leaves, the employer HAS TO revoke that H1 petition. Nothing new. This was always so. You can stay based on the timely filed "transfer" 2. Did not B tell you exactly what you are asking? 3. If you do not join, you can stay with A as B has made his approach clear. Safe is a relative term. 4. You can have any employer file your H1 and on approval leave and return with the H1 visa.