The day wheel rotates in 25.7 deg steps (360 / 14).
The date wheel rotates in 11.6 deg steps (360 / 31).
When you change the movement position from crown-at-3 to crown-at-4 you are rotating it by 30 degs (360 / 12). This means the day and date wheels will no longer align with the window at 3 since neither 25.7 nor 11.6 are factors of 30.
For the 6309 Seiko made two versions of each wheel, one for each movement position.
The date wheel rotates in 11.6 deg steps (360 / 31).
When you change the movement position from crown-at-3 to crown-at-4 you are rotating it by 30 degs (360 / 12). This means the day and date wheels will no longer align with the window at 3 since neither 25.7 nor 11.6 are factors of 30.
For the 6309 Seiko made two versions of each wheel, one for each movement position.