Simplify the following text for a Grade 6 native English-speaking person.
Original: Each week the theme of these shows change offering four hours of each genre once every 5 weeks in the same timeslot on BBC Radio 1 and BBC Radio 1Xtra . Every week this is followed by My Top 10 and 1Xtra 's Best of the Week at 5am and 6am before daytime programs resume on BBC Radio 1 and BBC Radio 1Xtra .
Simplified: Radio 1 also has a sister station , BBC Radio 1Xtra .