Tasks are archived in the farmerswife Server Setup > Bookings tab > Archive Tasks yyyy.
Click on the corresponding year to archive all Tasks on that specific year.
A confirmation window will appear asking to Confirm or Cancel the operation. After confirming a final pop-up will show the amount of Tasks that have been archived.
As a result all archived Tasks will disappear from the time lines (Hourline and Long Form). But will show again if they are restored.