Using Wall O’ Waters, I was able to plant tomatoes in the garden in mid-April, resulting in ripe garden tomatoes at least 2 weeks earlier than plants put in the garden on May 20th. It’s some work to set them up. They last for many years. This is what Wall O’ Waters look like:
(These are not pictures from my garden.)
Since the Wall O’ Water plants had a month head start, but produced only two weeks earlier, I don’t think planting even earlier will result in earlier tomatoes.