If you have been looking for a stationary trainer lately you most likely have come up empty. Trainers and rollers are a relatively easy and affordable way to convert your bike into an indoor exercycle. Now with the advent of "smart" trainers that connect to tablet or PC via Bluetooth or Ant+ you can utilize such apps as Trainer Road and Zwift, or even take a spin class.
Covid came along at precisely the time when manufacturers and suppliers were scaling down inventory for the spring and summer. As the weather gets better people that are housebound through the winter begin riding outside and demand for stationary trainers and rollers goes way down. Unfortunately with everyone being stuck indoors, the demand curve went up; way up. Most major manufacturers such as Tacx, Saris, Wahoo, and Blackburn quickly sold out of what they had, and getting new inventory has been difficult with factories shut down. Most are backordered for months.
If you have become frustrated with attempting to find one the best thing you can do is pre-order one. Retailers that place backorders and often pre-paid for them which puts them first in line for new stock. When will they return to inventory? Some are brands are saying a few months, some fall, some next year. There are so many factors slowing production and delivery right now it is hard to predict accurately.