If the RX460-to-RX560 is as uneventful as the RX480-to-RX580 change I just went through*, then I guess now is indeed the time to be looking for "end of line, clearance sales" on the outdated and obsolete
Honestly, as far as I can tell, the 400-series is the better product; AMD has taken a product that was already slightly above it's idea clock/voltage sweet spot and overclocked/overvolted it further for the 500-series.
* - I'm not stupid**. It was just a zero-cost-to-me opportunity that I was curious to investigate.
** - Well, not provably stupid; What happens off the record is something I'm unwilling to disclose.