text: -- +migrate Up
  alter table right_to_use alter column valid_from type timestamptz using valid_from::timestamptz;
  alter table right_to_use alter column valid_to type timestamptz using valid_to::timestamptz;
  
  -- +migrate Down
  alter table right_to_use alter column valid_from type timestamp using valid_from::timestamp;
  alter table right_to_use alter column valid_to type timestamp using valid_to::timestamp;
  