3a. Cheekie chappie at university (8) no letters as yet!!
11a. Go over - to the enemy once more? (12) R???????????
17a. Result of refusing to take things lying down? (5-2,5) ?????-??-??G?T
10d. Expanding, becoming more communicative (7,3) ???????-??T
Many thanks, struggling this week with it, normally finished it and posted by now!!