How far in advance are train tickets released?

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Tags

1. #earlier
2. #confirmed
3. #available
4. #advance
5. #choose
6. #preferred
7. #appear
8. #availability
9. #travel
10. #begin
11. #times
12. #before
13. #generally
14. #journey
15. #details
16. #weeks
17. #tickets
18. #planner
19. #retailer
20. #train