Hong Kong Visa for US Citizen with Chinese Visa L

Hi,

I will be staying in Hainan province for vacation. I recently discovered a 1 night cruise I would like to take in Hong Kong. But, I already told the Chinese consulate my travel plans. My children and I have our L Visa already. Question #1: Can I make additional travel plans within my pre-arranged visit? #2: Will I need a new Visa for Hong Kong? Wil I get in trouble for traveling around with new plans that I did not tell them before hand? I will still be staying at the same hotel and leaving on the same date. Thank you very much.