Hi
I'm afraid that no-one here can tell you anything about Apple's unannounced plans. You are not talking to Apple here - this is a user-based technical support community.
Whilst Apple no longer sells new Apple Watch (1st generation) models, no model of Apple Watch has yet been declared vintage or obsolete by Apple:
Vintage and obsolete products - Apple Support
Keep in mind (particularly if selling your Apple Watch, in order to describe it accurately to any buyer) that there is no "Series 0" under Apple's terminology: