CommentStreams:93ac86805d8c79320faa8bd162f536c4

yes, that is exactly how it works.

As long as you don't excite your mythic card from current tier to 5 stars, you will remain there as long as you want and keep getting duplicates of the current tier that you can use later...

Same is true when you go back from tier 3 to tier 1, as long as you don't excite mythic card to 10 stars you remain on current tier.