Late rent fees in Connecticut "CT"

[Sunny Rajvansh]

Hi,

I have a rental property and my lease says the rent is due on the 1st of every month and its late after the 7th. the late fees are $50 after the 7th. My tenant was paying me on the 7th of every month and since last 3 months tenant is paying on the 10th instead. First time she said her granny was sick and she is not around so it will be late and since then its been 3 months she is paying on the 10th. She told me in Connecticut landlord can not charge late fees until the 10th. I was wondering if thats true. 

When i did try to find online this is what I found at nolo.com

"Connecticut Rules on Late Fees

Rent is legally due on the date specified in your lease or rental agreement (usually the first of the month). If you don’t pay rent when it is due, the landlord may begin charging you a late fee. Under Connecticut law, landlords may not charge a late fee until nine days after rent is due."

Is this really true, isn't 10 days a long time? If my lease says late fees after 7th and tenant has signed it, can I still charge late fees after 7th? Also, if the rent is due on the 1st, what are my rights after the end of the day?