I picked up the writs on 7 characters yesterday and waited until today to turn them in. Was able to get boxes for yesterday's and today's crafting writs.
If you picked up some of the crafting a few days ago rather than Wednesday, you may have hit the cycle refresh since they repeat every three days. For example, if you picked the quests up on Monday but didn't turn them in until today (Thursday), it won't show as any new quests for today.
Has worked well on 6 caracters for me. 7+7I only got a total of 8 gifts. Last year I saved my writs from the day before, turned them in, did new writs and got gifts for all of them. Did the same thing this year but only got a total of 8 boxes. Tried two other characters and they didn't get gifts. I did the started mission for all of them. I didn't see anything about a cap in the announcement. Can someone clarify @ZOS_GinaBruno
I'm on PS4 NA. I haven't tried on PC yet.
I wonder if you need need to to have cake active for rewards?