This is my guess on order when creating/editing a post:
- acf/input/admin_enqueue_scripts
- acf/input/admin_head
- acf/load_field
- acf/load_value
- acf/prepare_field
- acf/render_field
- acf/init
- acf/input/form_data
- acf/upload_prefilter
- acf/validate_attachment
- acf/update_value
- acf/validate_value
- acf/validate_save_post
- acf/save_post
