We'll, at least she's old enough so it won't hurt her! Have you tried palpating to see if you can feel embryos? At a certain stage (I want to say 2-3 weeks after mating, but it's been a LONG time since I've bred rabbits... we raised and ate a lot of them back in the 1990's) you can easily feel them. Just gently squeeze the abdomen between your thumb and fingers, and they feel like very firm marbles.
You'll want to get a nest box set up and ready, just in case. It's generally not recommended to put a nest box in until 2-3 days before her due date, because if they aren't feeling the nesting urge, they'll use it as a bathroom. But in this case, without a solid due date, and cold weather advancing, it would probably be better to give her a box, and just be prepared to clean it and provide fresh bedding every couple of days. If you go to change it out one day and see some fur in it, don't clean it... just put it back quickly and let her do her thing.
One more thing... some does, especially inexperienced ones, don't pull enough fur to keep the babies warm. If she kindled, and the tiny ones aren't well covered, gently pull some fur from her chest area and add it to the next. You can even steal some from another bunny... supposedly they don't care about the odor. But when I had to do it, I always put a tiny smear of Vicks above her nose. By the time her sense of smell came back, the "strange" fur had already absorbed some of her odor. I filed that under "better safe than sorry"
We found we prefer chicken for eating, but rabbits can be an amazingly efficient (and stealth- quiet!) way to put meat on the table. One minor problem is the babies are so stinking cute!
Summerthyme