H1B After Using AP is Possible, No H1B Loss? --Xiao Baitu Please

I just called my friend who went back to China last summer with AP. Now AP is expired after one year. He extended H1B in January with the Premium processing and now he is still H1B with the same employer. How to explain this? He does not know how to do it because his lawyer did for him. Earlier someone said H status would be lost, and you have to use EAD to work. Any comment? Xiao Baitu please help. Do you really lose H status after using AP?