When's the best time to buy a TV, laptop or smartphone?
https://www.cnet.com/news/tech-release-calendar-when-to-buy-your-gear-apple-samsung-iphone/
Worst case, you know for sure you're not interested in the new model. Best case, you get the new model instead. Perhaps the company will discount the older model and you'll save some money. So that's, um, also a best case?
Below are some general timelines that should help you get a better idea of what gets released when, and when you can commonly expect to get discounts. Keep in mind that it's possible these dates will change, and sales can happen randomly throughout the year.