I decided to start a new save just for fun. I'm playing lilsimsie's curent Save File 4.0: https://www.youtube.com/watch?v=sB_U9p5S3m0
The issue I'm having though is that she had the seasons length set to 7 days. I wanted to set them to 28; I play on Long lifespan and 7 days is just too short, plus I want to make sure my Sim has time to go to Granite Falls to collect the herbalism plants down the road when she has a bit more vacation time. But now the game calendar is all messed up; it's still Spring but I'm showing Harvestfest next week and Winterfest/New Year's in the following. Is there a way to reset the ingame calendar or will I just have to wait till the next in-game year for it to return to normal?
Only the random holidays that pop up on the calendar like the Lottery or Rebate Day will reappear if you delete them. Fixed holidays like Winterfest or Love Day won't reappear. You have to recreate them if you delete them.
You have to delete all the holidays that are in the wrong season, and then recreate them in the correct season.
Fun must be always -- Tomas Hertl (San Jose Sharks hockey player)