When logging on into patch 5.4, you receive a quest that takes you to the Seat of Knowledge in Vale of Eternal Blossoms.
If you accept Chromie's quest to go to the island, she gives you a [Curious Bronze Timepiece] that allows you to teleport to the Timeless Isle.
If you then abandon the quest after teleporting to the Isle, you may go back later to pick up the quest from Chromie and teleport once again.
You may repeat this as many times as you want.
This allows you to bypass the waste of 7.5k Timeless Coins to obtain a trinket to accomplish the same task.
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