Two Double entry Visas in a row

I have a double entry permit since January (been to Hong Kong in Feb to validate the second entry) and I'm using it until March. Then, I'll go to Hong Kong during two weeks and want to apply there for a new Double entry tourist L type as I want to visit more places in mainland PRC.
Is it a problem or can I do as many entry permit I want in a row?
I read that if you already had one, you may apply only for 14 days. I hope not since I've booked flights, trains and hotels in Beijing, Guilin, Zhangjiajie, etc. If I show the papers of all theses reservations, may I have the regular double entry tourist L type for 60 days?