UPDATE: RUMOR: PS5 Dev Kits Sent Out This Year. Launch 2019. BC With PS1/PS2/PS3. Sony acquires Silent Hill. Blade Runner PS5 Game At PSX. And More.

[JRPGfan]

I hope PS5 does launch in Q1.... of 2020 :p

That way it can get launch boost + holiday boost in same year, which just makes much more sense.
Nintendo did it with the Switch and that worked out well enough.