Ask HN: Any advice on taking preorders?

We are considering taking preorders for our hardware product. We have enough potential users clamoring for it (our invitation list is a few thousand long) but, thanks to COVID, it looks like we have to order the most critical chips 6 months ahead. Our newest prototype isn't fully ready yet, though our MVP worked well. To get an estimate of how many chips to order, we are considering taking preorders. We don't want to take the crowdfunding route. However given the uncertain timeline we are worried about the ethics of taking preorders. Tesla does it, But they have credibility/deep pockets. So...thoughts?