Unlike all other Snowflake operators, S3ToSnowflakeTransfer requires the usage of schema instead of letting it be an optional variable that when passed would be used, and if not, then connection metadata is used. 

I can be assigned on this if needed. Keeping this up here so this doesn't go unnoticed. 
airflow/providers/snowflake/transfers/s3_to_snowflake.py
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"""This module contains AWS S3 to Snowflake operator."""
from typing import Any, Optional
from airflow.models import BaseOperator
from airflow.providers.snowflake.hooks.snowflake import SnowflakeHook
class S3ToSnowflakeOperator(BaseOperator):