The Apple Watch Series 10 will feature a larger display and a new chip, but new health monitoring features for the device are now in question, Bloomberg‘s Mark Gurman reports.

In the latest edition of his “Power On” newsletter, Gurman said that the design of the Apple Watch Series 10 is “unlikely to look much different” to its predecessor, but it will be thinner. Meanwhile, the Apple Watch Ultra will not get a new design this year.

The new Apple Watch “Series” models will continue to be available in two casing sizes codenamed “N217” and “N218,” and feature larger displays. One of the models will have a screen roughly as large as that of the Apple Watch Ultra.

Both the Apple Watch Series 10 and Apple Watch Ultra 3 will apparently feature a new processor that succeeds last year’s S9 chip. While this could “lay the groundwork for some AI enhancements down the road,” it will not run Apple Intelligence and there are currently said to be no plans to bring “the full initiative” to the Apple Watch.

Apple has been developing hypertension and sleep apnea detection features for the Apple Watch that were originally slated for release in 2024, but Gurman now says that the “effort hasn’t gone smoothly” and “Apple has run into some serious snags.” The hypertension detection feature has been insufficiently reliable during testing and there are concerns about integrating it into the refreshed design, which could force Apple to postpone this feature until next year

Likewise, the sleep apnea detection feature is now in trouble because it relies on blood oxygen saturation, which Apple Watches in the United States cannot currently measure due to an ongoing legal dispute with Masimo. Gurman postulates that the despute with Mazimo could be resolved by September, or Apple could find a way around it by arguing that the blood oxygen sensor could be used for purposes that are not directly related to blood oxygen levels. The company could also announce the sleep apnea detection feature and hold off releasing it until a later date.

Apple is also purportedly continuing testing and discussing the prospect of 3D-printed casings for some Apple Watch models, which could accelerate production and use less material.

Gurman says it is still not clear whether Apple will brand the new Apple Watches as special anniversary models or wait until next year, given that the original Apple Watch was announced in 2014 and released in 2015.