As far as last year, I tracked down the announcement for when Jack-o-turnip was enabled. 4 Oct 2021.

SMALL UPDATE / PATCH NOTES
POSTED
Mon, October 4, 2021
Patch 0.203.10
Further post-Hearth & Home-tweaks
This time we’ve made some more adjustments to make everything feel more balanced. Some food stats have been changed, but more importantly all melee weapons will now cost less stamina to use. We also taught the Fulings some new battle tactics and told night-spawning monsters to go to bed once the sun is up. And since fall is properly setting in, you can now make your home even cozier (or spookier) with a Jack-o-turnip!

0.203.10
* Oven & cookingstation drop food items when destroyed
* Gamepad sensitivity save fix
* Acorn & Birch seed drop rate increased
* Onion seed icon tweak
* Player number difficulty scale tweaks
* Removed comfort from Crystal wall
* Atgeir, Blackmetal axe, Bronze spear tweaks
* Lower melee weapon stamina drain
* Knives have more durability
* Tweaked some food stats based on effort to craft (blood pudding, boar jerky, bread, deer stew, mincemeat sauce, wolf jerky)
* Night-spawning monsters despawn faster in the morning
* Parry ranged attacks staggers caster again (illogical but fun)
* Fuling AI tweaks (Spreads out & circles more)
* Longer Lox attack cooldowns
* Frost damage slowdown fix
* Shield tutorial trigger fix for wood shields
* Wood log 26° & 45° stability fix
* Jack-o-turnip enabled
* Torch + weapon jog animation fix