Hey there,

I am really sorry for the delay of this reply as it is a weekend for us here.

The current Easysocial version is 2.0.14, it should be no issue when you upgrade your Easysocial from 1.4 to 2.x in joomla 3.4.8.

But to be safe, I would suggest you to setup a test site, so you can try upgrade it from your test site first in case any happen it will not affect with your live site.