Is '明天你都六点起床不起床？' a correct question?
&quot;明天你都六点起床不起床？&quot; is not a valid sentence in Chinese.
If we remove 都, and make it &quot;明天你六点起床不起床？&quot;, it is valid but a little awkward. Because we usually don't say things like &quot;起床不起床?&quot;, &quot;吃饭不吃饭?&quot;, &quot;睡觉不睡觉?&quot;, &quot;学习不学习?&quot; etc. when asking questions. The point here is that we normally don't repeat the whole word before and after 不 in questions, instead we simplify it.
Note: It is ok to repeat the whole word before and after 不 in declarative statements, like 老师喜欢不喜欢你，我真的觉得不是什么问题. While it can also been simpified as 老师喜不喜欢你，我真的觉得不是什么问题.
Here is the natual way to say it in Chinese:

起床不? or 起不起床?
吃饭不? or 吃不吃饭不?
睡觉不? or 睡不睡觉?
学习不? or 学不学习?

Back to your question, &quot;明天你都六点起床不起床？&quot; is not correct.
If you are asking a person of his/her get-up time in the moring, you would say:

你早上6点起床嘛? or 你早上6点起来嘛?

If the listener usually gets up at 7 o'clock, and you want to know if that person plans to get up at 6 o'clock tommorow morning, then you can say:

明早你六点起床不? or 你明天早上六点起来吗?