"Except for" vs. "except on"

I want to say that I have time to do the homework only on Sunday and on no other day.
So can you help me choose which of the following sentences are considered idiomatic and common for native English-speakers or, if none of my examples is acceptable, suggest what I might say instead?

1. Except on Sunday, I do not have much time available for doing the homework.
2. Except for Sunday, I do not have much time available for doing the homework.
3. Besides Sunday, I do not have much time available for doing the homework.
4. Other than Sunday, I do not have much time available for doing the homework.

Solution 1:

From each of your proposed sentences, I would assume that you have lots of time on Sunday, and very little time on any other day. If you want to convey that you have no time at all on any other day, you should say,

"Sunday is the only day when I will have time available to do the homework."

Solution 2:

Actually, none of your example sentences is idiomatic American English. Ironically, however, the first sentence of your question contains your answer: "I have time to do the homework ONLY on Sunday and on no other day". You might want to shorten the sentence to:

I have time to do the homework only on Sunday.

"For doing the homework" sounds a bit strange to me.

Solution 3:

3.Besides Sunday, I do not have much time available for doing the homework.

4.Other than Sunday, I do not have much time available for doing the homework.

Sunday is the only day available for me to do my homework.