It means you have 1000 long-distance minutes every month for 24 months.
You should also note that the minutes are only free for specific countries.
China (including Macau)
Edit: You can also keep track of the minutes in the Fido app. Fido has recently updated their minute tracker feature to include long-distance add-ons.
You should now start receiving notifications when you reached 75% and 100% of your minutes for the month.