The 28th was a auto-bonus that popped up (6 hours of 1 of the bonuses).
We traded that out and decided to overwrite it with a 24 hour double-bonus instead.
The experience bonus (200%) will begin at - Tue Dec 31 00:00:00 2019 The learning bonus (200%) will begin at - Tue Dec 31 00:00:00 2019 The experience bonus will end at - Wed Jan 1 23:59:00 2020 The learning bonus will end at - Wed Jan 1 23:59:00 2020