Jitterbug,there are several strains of Brandywine, I think I have about 9, my point is that they have different maturing times, most are main season, but there is one that is a liitle earlier so is a better bet.
Times below for comparison purposes only as it is US scale are days after transplanting out into it's final spot.
Yellow Brandywine...90 days
Yellow Brandywine...Platfoot Strain 85 days
Brandywine Sudduths Strain 85 days
Brandywine ( the one people are usually talking about) 80 days
Brandywine OTV 85 days
Brandywine red.(potato leaf) 80 days
Brandywine red ( regular leaf) 80 days
Compare this then to say
Tumbler 55 days
Gardeners Delight 65 days
Sungold 57 days
Big Beef, my favourite biggie 73 days
Beefsteak ( the original) 96 days
Picking varieties if you are growing outside is as important as taste.
Hope this is helpful to someone. XX Jeannine