It is a real pain in the ass and something you can't screw around much with so be sure you are ready to commit yourself to a twice daily schedule of fucking with your plants. You can stretch darkness a bit but not daylight. Daylight can be shortened within your timeframe but never lengthened. When you apply the darkness NO LIGHT can get in. Are you sure you are ready for 2 months of this?

You should expect the plant to double in heigth during flowering but allow room for tripling to be safe. It depends on the strain and environment. Direct sunlight is not needed all day. Mine usually get only 3-4 hours of direct and still get quite large. Some are grown directly under mesquite trees with little direct light but plenty of ambient light and they often have to be tied down to keep from overgrowing the 6-8' treetops. So no, direct sunlight is not necessary all day.