Changing the type of last_activity column when using database session storage in Laravel 5.5

I've just started using the database session driver in Laravel 5.5 along with PostgreSQL, and I've ran into a slight inconvenience.

I would like to keep the last_activity column as timestamp with timezone, but Laravel wants to write an integer into it, and it sometimes also attempts to delete from it based on an integer value.

I tried doing the following in my Session model:

public function setLastActivityAttribute($ts){
    $this->attributes['last_activity'] = date('c', $ts);
}

which works well for saving, but when Laravel tries to garbage collect the sessions it uses an integer value which causes a PDOException:

SQLSTATE[22008]: Datetime field overflow: 7 ERROR: date/time field value out of range: "1506794381"
HINT: Perhaps you need a different "datestyle" setting. (SQL: delete from "sessions" where "last_activity" <= 1506794381)

Is there any way I could specify a format or intercept the process to keep the timestamptz column type?

via Chebli Mohamed