We need this so that reverse sync reproduces these values correctly.
To handle this in the database, we have a composite type (dashed: boolean, value: timestamp).
Value is always valid and is equivalent to the old timestamp column,
but must be equal to start_time if dashed is true.
The only place we directly reference this column outside sheetsync is thrimshim, where we
always consider the value only.
We need this so that reverse sync reproduces these values correctly.
To handle this in the database, we have a composite type (dashed: boolean, value: timestamp). Value is always valid and is equivalent to the old timestamp column, but must be equal to start_time if dashed is true.
The only place we directly reference this column outside sheetsync is thrimshim, where we always consider the value only.