This is according to one of the reports that suggests that one of the models could be an upgraded version of the Switch, while the other could be a cheaper model. The cheaper model, if the rumors are to be believed, might be a handheld-only version of the Switch where the focus will be on portability and mobility, versus the current-gen version of the Switch which can double up as a home console and also a portable console.
Nintendo had previously denied that they were making a new console, but the company later softened up on their stance by stating that they were always working on new hardware and that they would announce something when they are ready. Whether or not that is the new Switch consoles is unclear, but all of this is certainly shaping up to look that way.
No word on when we might expect the console to be launched, but it is expected that Nintendo will probably have it ready in time for the holidays which should help boost the sale of the console.