I am struggling with understanding the difference in meaning when the definite article is used with certain time expressions:

He is coming back to London, but not until next year.

He didn't win the competition until the next year.

When should the definite article be used? I remember it could to do with denoting the period itself, as in "He has done it in the last year" (past 365 days) and "He did it last year" (2018). Or is it something else? What if I include the definite article in the first sentence or omit it the second?

This question specifically concerns using "until" with those words.

marked as duplicate by Barmar, David, Bread, choster, J. Taylor May 16 '18 at 23:17

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