Early Ripening Seaberry

I live in the mountains and have a short growing season (around 65 days). I'm wondering which Seaberry varieties ripen in August or earlier. In the nursery catalogs some Seaberry plants are listed as ripening in "mid September" or "late September", but many varieties don't have an estimated ripening date. I have some raspberry plants that never ripen before heavy frosts in the fall (around mid September) so if possible I want to avoid that with my Seaberry plants.

This would definitely be worth selecting for if you have room and time for a project. We got a bundle of 25 nice seedling plants from Lawyer Nursery that were really cheap, and I'll probably plant more next year. I'll keep my eye out "the one" that works. Maybe you can too and increase our odds.