Via: https://felicoz.com/en/2017/05/acf-import-repeater-field-values-csv-programmatically/
- Prepare your CSV file with columns matched to the repeater sub fields
 - ACF – create a csv file select field
 - ACF – set up the repeater field with sub fields
 - create a new post
 - From the post, upload your csv
 - create empty repeater fields depending on the number of rows you have in csv
 - In the front page, paste this php code: