Can egg incubation time be halved?

There are two routes to the 50% cut: an incubation booster, or the weekend acceleration event.

The booster is an option you apply to an egg's incubation, and it halves the duration. The acceleration event does the same job for free while it runs. Launch events include a period where egg hatching times are halved, and that window falls over the weekend. If you have long eggs queued, that weekend is the time to put them in the Hatchinator.

Halving is the big lever, and petting is the small one. Caressing an egg in the Hatchinator takes 10 minutes off its remaining incubation time, up to a maximum limit. Friends visiting your Homeland can pet your eggs too, so a busy Homeland trims a few more minutes off each one.

Not settled: Whether a booster and the weekend acceleration event stack into a cut bigger than half is not settled.