The forked from OpenWRT in May 2016 and are now already going back. I guess there's not much to gain from the code merge for end users except for a few bug fixes (https://lede-project.org/faq#were_there_any_technical_reason...).
Politically this could mean that either OpenWRT has moved and intends to improve regarding the issues that lead to the fork, or that the fork wants to return home either way.
I suppose at least both groups think their time is better spent together instead of separate, and I personally like these news way more than those of yet another fork...
Just wanted to put it more into context.
If there is a re-merge, it's going to be the LEDE base that is used. There are a half-dozen or more new devices supported in LEDE, an no new devices in OpenWRT from after the split (that I am aware of anyway).
https://github.com/lede-project/source/graphs/code-frequency
OpenWRT's repository had minor bug fixes in comparison.