There are so many registrations, in fact, that the FAA is planningf to take the website offline on Wednesday at 9 p.m. ET for maintenance in order to prepare for the influx of incoming drone registrations; the administration is anticipating 400,000 drones could be sold this holiday season. The drone registration will return online on Thursday at 6 a.m. ET, following the nine-hour maintenance.

On Dec. 14, the FAA announced all drones weighing between 0.55 and 55 pounds — including cameras and other payloads — would need to be registered before they could be legally flown in the sky.

Drones purchased after Dec. 21 must be registered before they are flown for the first time. People who purchased drones prior to then have until Feb. 19, 2016, to register, letting the FAA “trace the ownership of an aircraft in the event of an incident,” according to its website.

Penalties for those who fail to register their drones are stiff. The FAA says it could assess penalties up to $27,500, and criminal penalties are much higher; they include fines of up to $250,000 and/or jail time for up to three years, according to an FAQ.