Why not "It is time to come home"? The first rollover translation for "volver a casa" as a phrase is "come", and spanishdict.com translations of volver include "come back" along with "go back" in every case I see. Should I just report that it should be accepted, or is there some other reason it means "go home" and not "come home"?
Hora usually translates to time instead of hour, so in my opinion "time to return home" is a better translation than "the hour to return". Think about it, when was the last time someone said "what hour do we go home" in English?
Even in English, they usually mean the same, so it doesn't really matter. "The hour is upon us!!!" means that "it is almost time."
I don't think so based on this forum, but I could be wrong. http://www.spanishdict.com/answers/118988/es-hora-vs-es-la-hora-vs-es-tiempo
First of all, "al" can only be used with masculine nouns "la casa" is feminine, so it would be "a la casa". http://www.studyspanish.com/lessons/contr.htm
However, the definite article "el/la" isn't needed in this case, when you talk about going home you can just say "a casa". http://www.wordreference.com/es/en/translation.asp?spen=regresar%20a%20casa