Got the 1.2.0a working from europe
im getting my steps from this excellent guide, just use the new files and everything works like a charm. source: https://www.reddit.com/r/SwitchPirates/comments/fsyqii/guide_how_to_get_acnh_easter_event_on_pirated_copy/
(1.1) When not already done, download JKSV.nro and put it in the "switch" folder on your sd card. (https://github.com/J-D-K/JKSV/releases)
(2.1) Optional: Backup AC:NH, just in case. JKSV -> Device -> AC:NH -> "New" Confirm with "A", when it dont work, press L+R while pressing "A" should do the trick.
In JKSV choose BCAT -> AC:NH -> "New" Confirm with "A", when it dont work, press L+R while pressing "A" should do the trick.
Turn off switch, remove sd card and mount in on computer. Open the JKSV folder, then AC:NH, then your BCAT folder (called BCAT - Date @ Time)
Now download the bcat files. Open the zip file and copy the "directories" folder to your BCAT folder. Now you should only have a "directories" folder and a "passphrase.bin" file in your folder. Delete everything else.
i got the files here: https://drive.google.com/file/d/1oiwxD6_GH464DBnGpjQyH2WPyLp287hw/view?usp=sharing
when it states that the files are temporarily unavailable because of high traffic just wait 24h or google for "bypass google drive download limit"
Put sd card back to your switch, start JKSV -> BCAT -> AC:NH -> Choose your backed up folder and press "Y" to restore. !!! Remember to restore your BCAT save, not the "DEVICE" save, that will mess up your game!!!!
When you Restart the game, you should see, that the version number has changed to 1.2.0a. The letter marks, that it worked almost. When you now start the game you should get a message, that a new event is taking place.
When the event dont work close the game, set your clock in switch setting back to time before the event. Enter the game, save and exit again. Now set your clock back to current time (or time from event when you want to play a passed event), everything should work now.