Sorry to trouble you usual lot, but try as I might I can't get the last three:
22a. Liberal gets behind Conservative in dispute (6). I have C - M - - E
6d. Veteran lost in study that's earlier written up (5). I have TYNE-. Tynes?
20d. Channel Tunnel's latest featuring in series. I have - - UIT. I can only think of fruit and Inuit and neither seem to fit the clue, although Inuit is closer letter-wise.