Applying h1B while H4 is pending decision

[piya]

My husband was working in US in his L1B visa. Since he got an RFE when applied for L1B extension, he initiated a change of status to H4 as my dependent by filing a I539. He requested his employer's law firm to submit a withdrawal for his L1B extension. The H4 status is in "Initial review". Meanwhile his employer has initiated filing a fresh H1B for him.

If his H1B petition is approved does he have to go back to India and get a stamping for his new H1B or he can start working on his H1B once its approved.

Please advise what action needs to be done on the current H4 change of status petition once he gets his H1B.

Thanks in advance.