Timemachine Data Disappeared? Sparsebundle OK
Early in December 2015, I upgraded to a new MacBook Pro. I kept the same computer name (I'm no longer using the old one) and when I set up Time Machine I opted to inherit the backup data dating to early 2014, nearly 2 years of data was backed up. Fast forward to January 3rd, 2016, I noticed my laptop was doing a complete back up which seemed strange. I had been using it for a month already. I noticed soon after that when I launched Time Machine the oldest back up available was starting January 3, 2016. I was not happy that almost 2 years of data just vanished. I went to my Time Machine back up drive and checked the sparse bundle which has the same name as my computer name, the previous one and current one (there is only one Sparse bundle). The files inside of it date to early 2014, which makes sense. But, when I launch Time Machine and try to move to the older dates to see the back ups from 2014 and 2015, all I see are black screens. Would Time Machine have deleted all of that data by itself? I can understand deleting an older back up or two as disk space is needed, but all of them? I'll note too that there is plenty of disk space available, over 1.5 TB, so that is not an issue.
Any ideas are appreciated as to why my data would have vanished, and perhaps how I can get it back? Is an undelete application a possiblity? Thank you.
MacBook Pro (15-inch 2.4/2.2 GHz), OS X El Capitan (10.11)