Well, it does not matter much, IMO.
The 8 to 12 weeks is just ball park numbers. There is roughly ONE week difference between sowing and germinating. I , personally count from sowing date and make a record of it in my gardening book.

On your other question, I will refer it to the more experience fellows. But in general, it would be best to avoid root bounding and it can be done by re potting to bigger pots.

Seysonn

A week or two difference between sow and sprout IMO is really insignificant. Anyway, with that said, I think in most cases it includes the germination time (I think).

I find that the most important thing to maximize production in our relatively short summer is to get the most growth you can indoors. Keeping in mind how much space you have under the lights and how big of pots you can go with. My plants last year were all germinated by the middle to late part of January. And by the time the first week of May came around they were fairly large (up to a foot tall) and crowding each other big time. Many had flower buds forming which is good. Got them adjusted to the outside without any sun burn, damage, etc. They were in tall 4" square pots after being transplanted from 3", and ended up with a pretty good rot ball, to much for 4" pot they were in. But the plants were doing awesome.

My problem was that on the 3rd week of May, here came along two straight nights of moderate to heavy frost. My attempt to save my plants by covering them worked, but quite a bit of foilage was still damaged or killed and every single flower bud fell off from the cold shock. It resulted in taking several weeks longer to the start of pod production.

The point I'm trying to make, is get the most growth you can before planting outside but don't put them out until you are absolutely sure.

I had a good ending though, as several of my plants grew to over 6ft tall and had huge pod production. Good soil helps also..

I plant directly in potting soil indoors. Day 0 is the day I plant the seeds.

Thanks all for the replies. I will be starting again indoors this year, although a bit earlier than last year. I am going to try starting in 1 1/2" rockwool cubes this year on a few, but as for lights, they only get what is in the south facing window. I do however plan on removing the plastic and installing window screen so it doesn't get as hot and gets a bit more air circulation. And as for pot sizes, the biggest I had last year was Solo cups with a few smaller and only a couple of 4" pots. If I put them too low, they get no light, but I guess I could rotate the trays daily. And yes, the screen or some type of shielding around the greenhouse is necessary due to a very curious feline that also resides here with us. Anyways, thanks again for the help.