In case you think I can never do the crossword, I have finished today except for 1d. One imposed on pensioner supporting us soldiers (3,4)
If 1across is uproot then the letters are
U ? E, ? O ? P. I thought the first word might be use as in one imposed on, but the rest is a mystery unless the second word is corp. Of course 1a may not be uproot in which case the first word may be THE.