This is what reorganize looks like in your debug.log
received block 7b4f07b84a9673bde2a8
REORGANIZE
REORGANIZE: Disconnect 1 blocks; 654e87f8a4164959c90e..42edae4346499d1df322
REORGANIZE: Connect 2 blocks; 654e87f8a4164959c90e..7b4f07b84a9673bde2a8
REORGANIZE: done
SetBestChain: new best=7b4f07b84a9673bde2a8 height=2645321 trust=4140918293389501583 date=01/26/18 17:44:55,block hash= 7b4f07b84a9673bde2a80f2078c8e52d1d89c72eabd5b0ea3e1b868080451c80
ProcessBlock: ACCEPTED
Essentially what is going on here is a new block comes in "7b4f07b84a9673bde2a8" The wallet disconnects the old block at "42edae4346499d1df322" and then sets the new block as the new best. This is at block height 2545321.