After years of incremental changes to the iPhone, Apple is mixing things up much more dramatically. Later this year it’s expected to introduce an ultrathin new device, followed by a foldable phone expected in 2026. Also next year, Apple plans to change its release strategy, launching pricier, more premium versions in the fall as usual, but pushing the release of the more affordable standard model to the following spring.

Apple’s hope is to rejuvenate long-stagnant sales of the iPhone, its flagship product, which accounts for more than half its revenue. But there are risks involved in the upcoming changes. The level of consumer demand for the new thin iPhone is so uncertain that Apple’s manufacturing partners in Asia are dedicating only about 10% of their production capacity to the new model, according to two people with direct knowledge of the matter.