Thanks! I just set up the reminder. It really should be opt-out but I'm sure Amazon knows what it's doing... Also curious if Amazon will send it's customers an email regarding the price increase (regardless of their settings).
Also strange... it also states on the left-hand panel (as of 27apr18, 1pm PDT):
> Next Payment: On September 25, 2018, you will be charged $99.00 for a year of Prime.
From all the articles I've read regarding this, the cut-off date for existing prime customers is June 16th. If I'm to be charged $119 on Sept2018, it should already be noted on the Prime Pages. Seems like a user-hostile action on Amazon's part.