Volunteer Mystery Lettuce

I'm not sure where this self-sown lettuce came from, but I'm hoping it'll overwinter here. When the original plant started getting big last Spring/Summer I thought it was from some seeds that had been shared with me. But when that plant went to seed, I saw that it had black rather than white seeds and that the seeds weren't retained within the seedheads but dehisced (were released like a dandelion or wild lettuce does). So, it's not what I thought it was. I'm guessing it's got to be from one of the countless packets of lettuce seeds I've bought over the years and blended to plant for "baby lettuce" use. Some of these would occassionally regrow and set seeds. Whatever the case, I hope it overwinters. I've always wanted to have a lettuce that would do that here. I even used to play around with 'Paris Island Romaine' X prickly lettuce (Lactuca serriola) crosses in an attempt to get an edible lettuce with the winter-hardiness of the wild stuff. I got the hardiness, but never got around to getting the prickles and bitterness bred back out. Maybe this volunteer will get me to that cold-hardy lettuce without having to use the wild stuff. We'll see.
If not, a few months back, I also dumped all of my old bought packets of lettuce seeds together and planted the mix out in the garden. Some of what came up is still alive but really small. Maybe some of these will overwinter.