Intentionally Enters the State of Janaba
Question :

During the month of Ramadan, if somebody knows that he will not be able to perform ghusl until dawn and he intentionally enters the state of janabah, will his fast be valid?

Answer :

The fast is not valid in the said case.

The Ghusl of Touching the Corpse
Question :

If a person is required to perform the ghusl of touching the corpse, but does not do so until after dawn, can he fast that day?

Answer :

The fast is not nullified by this, so he may fast.

Ignorance of the concept of Janaba
Question :

I was ignorant of the concept of Janaba, and did not know that ghusl was obligatory if it happened. During the holy month of Ramadan, I kept my fast without doing ghusl of Janaba. A few months later, I came to know about ghusl and performed it. What should I do in regards to the previous fasts?

Answer :

There is no kaffara for breaking the fast in the said case. One should make up the fast before the next Ramadan.
If he does not make them up before the next Ramadan, an amount of 900 grams of dates, wheat, floor, rice, lentils and the like for every missed fast must be given to the needy people as Fidya.

Remaining in Janaba until Fajr
Question :

A brother was in the middle of his month-long continuous Kaffara fasts. One night he had sexual intercourse with his wife and entered the state of Janaba. He then went to sleep with the firm intention of waking up before Fajr and performing the ghusl. He did wake up some time before Fajr, but dozed off again setting his alarm for another 15 minutes. When his alarm woke him up, he fell asleep again perhaps thinking that he will wake up shortly, and remained asleep until after Fajr. Is the fast for that day valid, and if it is, must he restart the fasting?

Answer :

What you have mentioned is not considered as deliberately staying in the state of Janaba. The fast is correct with the intention of fasting and the completion of the fast during the day.

Remaining in Janaba until Dawn
Question :

If one remains in the state of Janaba until the Adhan for Fajr prayers during the month of Ramadan out of ignorance, is his fast valid?

Answer :

If he did not know that deliberately staying in the state of Janaba until dawn nullifies the fast, then it is valid.
It is also valid if he did not know that he was in the state of Janaba until after dawn when he realized it.