Cheryl,
Radiation is given in fractions for 2 reasons: 1. A total dose (like 70Gy), all at once, would be fatal and 2. to allow the bodys normal cells time to recover and repair themselves.

A typical presciption for RT (radiation therapy) would be somewhere in the neighborhood of 60-70 Gy for H&N cancer. This would be broken up into fractions of 1.8-2.0 Grays (Gy)/day. Some treatment protocols call for twice daily treatments. One in the morning and one in the afternoon would be typical. Combined they still would not exceed the maximum of 1.8-2.0 Gy. You can roughly calculate the number of days in treatment by dividing the total number of Gy by 2. It will not change the number of days whether you opt for daily full fraction or daily X2 1/2 fraction. The latest NCCN oncology practice guidelines recommend the twice a day plan for many H&N cancers. 2 treatments per day is becoming more common and it's efficacy has been proven. Others here have had twice daily treatments.

This is a primary treatment plan and if it were me, and I had a T4N2cM0 staging I would go to a CCC or NCI Cancer Center as others have suggested. You need to hit this with the best treatment and expertise you can, particularly with a coordinated medical team. Others here have forgone treatment at a CCC for the convenience of not having to travel and they died. Some CCC's can arrange housing for you. I traveled 60 miles a day to go to a CCC in horrific bay Area traffic (some of the worst in the US).

I am not trying to frighten you but this is an aggressive, ruthless cancer and you don't get many chances to combat it. Radiation Oncology is like any other specialty and some are better than others. H&N cancers are relatively rare, in the scheme of things, and that's why your odds will be substantially better at a CCC where they see a lot of H&N cases. I sometimes use the analogy would you bring your BMW to a Toyota dealership for service?

Incidentally, the extractions need to heal first before they will start treatment. It was almost 2 months from my original Dx to when I actually started treatment- and they fast tracked all of my labs and scans.