I have blocked my son's laptop begining at 8pm. I have also set his daily limit at 3 hours. I have sat by as he has continued to use the device both when the time has gone past 8pm and after 3 hours. I thought I saw in one of the topics that I have to choose one or the other; I can't both set a time limit and block the device after a certain time. Ok. It is not working consistently. Sometimes it works, most of the time it doesn't. The other day I told him to finally get off the laptop and I got an alert a few hours later that he was blocked; I had already told him to get off the laptop hours earlier.
The reason I paid for this was so the laptop would shut him out after a certain time.