Version confusion aside, the changes listed for Opera 49.0.2725.56 appear to be minor bug fixes. Which is weird, because the new version announcement mainly talks about improvements to Opera’s built-in VPN (Virtual Private Network) feature. The updated VPN service is apparently faster and better; it’s also now hosted on Opera’s own servers instead of SurfEasy’s.
If you use Opera’s built-in VPN, version 49.0.2725.56 may be worth exploring. Otherwise it’s unlikely to be of much interest.