At 8:05, you are spot on with your fuel marker that your fighter on MAP only had a range of 1. You count, "1, 2..." This would have been too far if you flew over Japan, but your move was still legal because sea zones P15 and P16 are adjacent. So it was just one move. 8 )
At 10:30, you place a heavy battleship in sea zone P15, but you didn't have one at stage 2. It was at stage 3. So I have you with 4 heavy battleships in sea zone P15, one at stage 3 and one at stage 2.
Reviewing Japanese Heavy Battleship production. On T10, you start your first HBB. T11, you advance it to stage 2. T12, you start 2 HBB and finish your 1st. T13, you start 1 HBB and advance 1 to stage 2. This means you end T13 with 2 HBB at stage 3, 1 at stage 2, and 1 on the board. T14, you start 1 HBB, advance 2 HBB from stage 3 to stage 2, and place your 2nd HBB on the board. T15, you finish the 2 HBB at stage 2. At this moment, you have 1 HBB at stage 3 and 4 HBB on the board. This turn, you purchase 2 stages of HBB. 1 HBB is started and the one at stage 3 advances to stage 2. You have 4 HBB on the board.
At 8:05, you are spot on with your fuel marker that your fighter on MAP only had a range of 1. You count, "1, 2..." This would have been too far if you flew over Japan, but your move was still legal because sea zones P15 and P16 are adjacent. So it was just one move. 8 )
At 10:30, you place a heavy battleship in sea zone P15, but you didn't have one at stage 2. It was at stage 3. So I have you with 4 heavy battleships in sea zone P15, one at stage 3 and one at stage 2.
Reviewing Japanese Heavy Battleship production.
On T10, you start your first HBB.
T11, you advance it to stage 2.
T12, you start 2 HBB and finish your 1st.
T13, you start 1 HBB and advance 1 to stage 2. This means you end T13 with 2 HBB at stage 3, 1 at stage 2, and 1 on the board.
T14, you start 1 HBB, advance 2 HBB from stage 3 to stage 2, and place your 2nd HBB on the board.
T15, you finish the 2 HBB at stage 2. At this moment, you have 1 HBB at stage 3 and 4 HBB on the board.
This turn, you purchase 2 stages of HBB. 1 HBB is started and the one at stage 3 advances to stage 2. You have 4 HBB on the board.