Lower case insert statement on incremental model

I have a number of models running on Snowflake where I need to integrate with tables originating from other sources. These have all lower case column names.

The models are incremental, and the end game insert statements also need to end up as lower cased.

This does not seem to be the case even though my selects are all aliased by column to be lower case (… as “id” etc).

How can I get around this issue?