The Apple Watch 6 is expected to be announced today, but the scarcity of older models seems to confirm that news of Apple's smartwatch is on the way.

As 9to5Mac discovered, the Apple Watch 5 is becoming increasingly difficult to purchase. It's as if Apple is intentionally not replacing inventory and trying to get new ones on the shelves.

This started in a sense a few weeks ago when less common Apple Watch 5 options such as metal bands and ceramic or titanium cases began to disappear. But now even the basic model, with its aluminum case and white fluoro rubber band, is hard to find.

9to5Mac checked local Apple sites, and apparently these shortages are affecting the US, China, and Japan. Availability in Europe, however, is still normal.

Consumer tech companies have limited warehouse space to store their products, so it is common for them to clear out old gadgets before new upgraded devices are released. That's why everyone gets excited about these seemingly innocuous "out of stock" notices.

All of this adds fuel to the fire that Apple will announce the Apple Watch 6 today via a low-key press release. This rumor, often attributed to reliable leaker Jon Prosser, seems out of character for Apple, which has released the latest Apple Watch and iPhone models simultaneously every year since the Apple Watch Series 2 in 2016.

This year's Apple Watch upgrades are especially interesting given that the Apple Watch 5 was only a slight improvement over the Apple Watch 4. New upgrades should include SpO2 monitoring, improved sleep tracking, and possibly new mental health tracking features. Meanwhile, the Apple Watch 6 is also rumored to change its primary control method from a digital crown to an optical sensor.

A second new Apple Watch model may also be on the horizon in the near future; rumors of the Apple Watch SE, an entry-level smartwatch with a faster processor than the Apple Watch 3, have recently surfaced.