Locked twice

Friday's Sudoku puzzle from Toronto Star gets locked twice. Here is the original puzzle on 10 October 2014 by Pappocom:

After only 7 steps it gets locked like this:

The key to this first lock lies in the first row. The last 2 cells (columns H and I) have only 3 and 8 as candidates. Thus, 3 and 8 can be eliminated from the rest of row 1, particularly in cell A1. This leaves A1 with a lone candidate, 1. Also, only one location remains to place 8 in column A, on A6.

HI1: 38 N
A1<>8 R
A1=1 N
A6=8 C

With two more steps, the puzzle is locked again.
D5=8 BC
B6=5 N

The key to the second lock lies in the 4th row. The last 3 cells (columns G, H and I) have only 1, 2 and 8 as candidates. Thus, 1, 2 and 8 can be eliminated from the rest of the block (and the rest of the row too). In particular, 1 and 2 are eliminated from cell G6, thus leaving 7 as the only candidate.

GHI4:128 N
G6<>12 B
G6=7 N
D6=2 R
F1=2 BC
H2=7 B
H7=9 C
E9=9 BC
... to the end.

Jammed Puzzle - Set 5

Find the single move in each of the 4 jammed Sudoku puzzles.  A jammed puzzle has only a possible move (without using elimination techniques). See how fast you can find the single step in each puzzle.

For more information: First article – Sudoku Puzzle Notation
For the solutions: Spoiler Page

 

Grapefruit A B C D E F G H I 1 6 2 2 6 3 1 6 4 4 6 8 4 9 3 5 1 8 6 4 6 4 7 6 1 8 9 7 1 6 5 8 8 2 6 9 1 6 9	Strawberry A B C D E F G H I 1 6 3 2 2 3 3 2 7 5 3 6 4 3 6 4 2 9 1 5 6 3 6 7 2 1 9 3 6 7 3 5 8 8 3 9 2 4 3
Redcurrant A B C D E F G H I 1 8 4 6 7 2 6 8 3 3 7 3 6 5 8 4 7 1 9 5 8 7 5 6 5 3 7 7 6 7 1 8 4 8 7 6 9 8 9	Clementine A B C D E F G H I 1 3 1 5 2 5 1 3 3 5 9 1 3 4 7 6 5 9 5 5 1 6 6 6 8 5 7 1 9 5 8 5 9 8 5 4