Oracle promised to retire the Java 11 1Z0-815 and 1Z0-816 exams at the end of September, and it seems they have kept their word. The links for these pages no longer work. It's as if Oracle erased their existence entirely! The replacement for these two exams is the single 1Z0-819 Exam. Luckily, the 1Z0-817 Upgrade Exam is not impacted.
I have mixed feelings about this change. Ultimately, I wish they had started with a single exam, rather than making the OCP require two exams. I think it made sense when they had an Associate and Professional certification titles, but when they dropped the Associate certification title, it made less sense to still have two exams.
To all those who contacted Oracle about extending the expiration notice to longer than a month, you have my respect. The change is easily the biggest and most drastic change in any Java exam to date. After all, the 1Z0-815 and 1Z0-816 exams had only been out a year.