Plant them.

Bulbs can be planted up until before the ground freezes.
Just look at the package and recommendation when to plant, based on the USDA zone map.

Planting too early is not going to do much good. They have to overwinter.

I have some Darwin tulips in the ground that have been coming up every year for at least ten years....

In zone 8, the soil really doesn't freeze - a hard frost may make it crisp and crunchy the top inch or so but that's it.

Planting any time after the bulbs are available in the nursery and in stores is fine. And you could continue onto the end of December for most spring blooming bulbs - much later than that and you miss the timeframe for vernalization and flowering. Planting early is less of an issue - the bulbs still have the winter to look forward to and if from previous seasons, they've been hanging out all summer anyway.

Darwins have a better reputation for returning than most of the hybrids. I might be reluctant to plant with a containerized Japanese maple as these trees will need water in summer, whereas the tulips would prefer it dry(they perennialize much better if kept very droughty through their dormancy). Also, if the tulips didn't return well, then you'd have to go to the trouble of digging and replanting with something else. And JM's hate root disturbance.