Are Tibet permits being issued again?

I have been planning to go to Tibet in August. I've read online that Tibet permits weren't being issued in July, but the local travel agent (in Shantou) says foreigners can't travel to Tibet in July or August. Is the travel agent right or are they letting foreigners back into Tibet in August?

Also, I'm a little confused about the tour requirement for getting a travel permit. Do I need to be with a tour group on the train as well, or can I travel on the train by myself and meet with a tour there? Do I have to be with a tour group the whole time I'm there? What is the purpose of this?