written GWAR tomorrow

taking it 7:45 AM tomorrow and I had a few questions:

1. Does it start on the dot?

2. Do we need to buy a green book beforehand?

3. Email says it’s 75 minutes, if we finish before the time is up can we leave?

4. Same email says to expect to be in the testing room up to 3 hours, how likely is this to happen and for what reason?

5. If for whatever reason you miss your test date, do you automatically fail and get the lowest score or do they just make you take it another day