Only direct shareholders whose shares are NOT held in Street Name by a broker were sent the ShareHolder Letter (like Certificate holders). In other words, only the shareholders the Transfer Agent has the Name and Address (Contact Info) were sent letters.
Since the Imgur images are hard to read, a transcription was provided courtesy of Xlogit3k:
Xlogit3k Transcription of the letter. Last paragraph of the Letter confirms that recent 10-K and 10-Qs were at FINRA's request. Name Change expected by August 25, 2017.
A name and ticker change are effective one day after they are posted to FINRA's daily list. Bong's post suggests name and ticker change will happen within a few business days, based on ETrade's past experience with notification from the Depository Trust Company (DTC).