"by when" vs. " until when"

[cubisto]

Sentences with "by when":
By when do I have to get there?
By when do I have to have it memorized?
By when do I have to enrol?
By when do I have to let you know?
By when do I have to generate this amount?
By when do I have to submit the report?
By when do I have to decide?
And by when do I have to do it?
By when do I have to leave Hong Kong?
By when do I have to turn this in?

Does "until when" also work:

Until when do I have to get there?
Until when do I have to have it memorized?
Until when do I have to enrol?
Until when do I have to let you know?
Until when do I have to generate this amount?
Until when do I have to submit the report?
Until when do I have to decide?
And until when do I have to do it?
Until when do I have to leave Hong Kong?
Until when do I have to turn this in?

If there is any difference, please be so kind and explain this to me.
Thanks for your help.

 

[GoesStation]

Remove by from each sentence and they'll be correct and natural.

Until doesn't work in any of the second set of sentences.