Well, daily from the 19th onwards. 19th onwards, rumoured giveaways (no official confirmation as of yet).  
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12-19 - The Lord of the Rings: Return to Moria
19 - Vampire Survivors
20-?
21 - Assassin's Creed Mirage
22-?
23-?
24 - The Evil Dead (Repeat)
25 - Mafia II: Definitive Edition
26 - Drone Swarm
27 - Doki Doki Literature Club Plus! (Repeat)
28 - Doors of Insanity
29 - Alan Wake Remasterd
30 - Grime (Repeat)
31 - A Virus Named TOM
1.25 - Figment 2: Creed Valley
9-9.25 - Rockstar Game