@adam_t why not just have each column (section) be a time of day (like morning, afternoon, etc) and then use the filter on the board to only show tasks due today?
If columns (sections) need to represent days, my other suggestion would be to use a custom field as your “time of day” and then you can sort the columns by that field. That would require a premium subscription but might achieve what you desire.
I understand what you are specifically looking to achieve, another break within tasks, but that feature is not yet available. You can upvote this feature here: Ability to add sub-sections
Another workaround you’ll see in the thread above, is to use unique characters as a “separation task” just like you did with LUNCH in your screenshot. Perhaps list it as “ ------LUNCH-----“ or 
LUNCH “ so it stands out more as a subsection.