URC set dates for festive fixtures
Ulster will play their festive interprovincials against Munster and Connacht on 20 and 28 December respectively.
When the United Rugby Championship released their fixture list in May, the traditional Christmas derbies had been listed without dates or kick-off times.
Leinster will host Connacht at the Aviva Stadium on 21 December before Leo Cullen's men travel to Thomond Park to face Munster on 27 December.
In another change, Ulster's away game against the Lions in Johannesburg on 28 September will now kick off at 11:55 BST.
URC festive interprovincials
20 December: Ulster vs Munster, 19:35 BST
21 December: Leinster vs Connacht, 17:30 BST
27 December: Munster vs Leinster, 19:35 BST
28 December: Connacht vs Ulster, 19:35 BST