Thanks for the post. I was unable to reset my system date, but I found a workaround and wanted to share for any future viewers. I found that the codes listed in the paste bin above (http://pastebin.com/L3c3rySj) had a pattern. Every month/day combination shares the same last 4 characters. So it's the year that changes the first set of characters, and these characters repeat.
For example:
At the password prompt, press alt+r
Take note of the date displayed. For me it was 2017-05-11
Use Ctrl+F to search the paste bin for your month and date. I used "-05-11"
Use the codes you find until one of them works. Mine was the same code as 2007-05-11 from the paste bin.
It looks like the codes might repeat every 10 years. So I would suggest starting with the month and date combination from 10 years prior to whatever date is displayed after you press alt+r.