Complex sentence: BCE & Astral announced that they have extended the closure of the their deal for Astral Media to December 16,2012, allowing BCE and Astral to adjust their takeover deal with the elimination of certain assets.
Split into simpler sentences: BCE & Astral announced that they have extended the closure of the their deal for Astral Media to December 16,2012. It will allow BCE/Astral to adjust their takeover deal with the elimination of certain assets.