According to Mike Johnson of PWInsider Elite, Rey Mysterio is very close to making his WWE return.
Apparently, the company wanted to bring the legendary luchador back a lot sooner but Rey's commitments to the ALL IN event as well as Chris Jericho’s upcoming Rock n Wrestling Rager At Sea prevented him from making a comeback.
However, Rey is expected to show up on WWE TV at some point over the next few weeks - though it may only be a one-off appearance to tease his full-time return later down the line.