Indicates that an action or state continues until a specific point in time.
When to use
waiting, confirming appointment time, checking duration of action
The nuance
Attach -(으)ㄹ 때까지요 to a verb stem to emphasize 'until (someone) does something.' It is mainly used to ask or inform how long an action will continue. For example: 기다릴 때까지요 (until I wait), 먹을 때까지요 (until I eat). It is not used with past or present tense but with future or volitional forms.
