I checked, and it seems to be a date-thing, you have entries of tips in the DB for 25/01 and 27/01, but none for 26/01 (nobody seems to have). The bots are always using UTC timezone as a reference, so that might be the reason why it appeared weird. Do keep an eye on it and let me know if you notice it again!

!LOLZ
!WEIRD
!DOOK
!MMB
!INEEDSLEEP