Currently, it's not officially planned, but if you know where to look, you can install mods that add a 2013 client. I might be wrong, but the current ones I'm aware of are either no longer updated or down.
If you want to find a working one, there are some abandoned Novetuslabs clients.
It also comes with 2014 and a semi-broken 2015 client. I don't recommend using them since they're outdated and basically dead, but here's a drive link I'm hosting that includes all 3 versions: https://drive.google.com/file/d/1E45lwTT-zrZZNo_-Q_-keI2wJTScLF3O/view?usp=shari...