link multiple gone, and ridiculously slow linking since latest update

v 28.7 (64 bit)

Recently, and I'm assuming it's to do with the update, I can no longer select many linked objects and relink them all. At some point we've been made to do these one by one, but even worse now when you relink the first one, everything gets deselcted.

Further to this, relinking an object now takes on average 13 seconds for it to change. 

These changes have been a pain before, but I've been able to deal with them, but this 13 second wait for every relink, which is what most of my work entails, is absolutely destroying my workflow.