The Apology Day/Weekend is a spontaneous event set up as compensation for a rollback. During the event, IAP (In-App Purchases) will give 25% more gems, and all players have a chance of receiving a lucky drop when breaking blocks. These lucky drops are indicated by a small red flash, and they give the item itself, it's seeds, and a gem drop of a higher value than what one would usually get from the block. This bonus only applies to blocks which normally drop gems and seeds. It also gives Lucky! Mod to all players until the end of the day.
In addition, a special item is usually available during these events to commemorate the work lost to the rollback prior. The Rollback Plaque, Rollback Plaque II, Rollback Plaque III, Rollback Plaque IV and Rollback Plaque V were available for the 1st, 2nd, 3rd, 4th, and 5th Apology Weekends respectively.
5 Apology Weekends have been issued so far: one for the weekend of February 23, 2013, one for the weekend of October 5, 2013, one for the weekend of August 10, 2015, one for the weekend of December 13, 2017, one for a single day on July 15th, 2018 and one for the weekend of February 14th, 2019.
See main article: Rollback