Are these sentences natural? If not, how would you say them?
I'll be occupied until evening today. and I'll be occupied all day today.
I'll be busy until evening today. and I'll be busy all day today.

Question

Are these sentences natural? If not, how would you say them?
I'll be occupied until evening today.  and  I'll be occupied all day today.
I'll be busy until evening today.    and   I'll be busy all day today.

Answer

I think they're all fine except for "evening", I would make it "the evening" in both.

Answer

I'll be occupied until this evening.
I'll be occupied all day today.
I'll be busy until this evening.
I'll be busy all day today.