found that this.sameFormFieldsAsArray option in application.cfc does nothing in case for name="zxc".
"myphones" varable, by default should be of type List but it is Array
Setting sameformfieldsasarray to false/true in application.cfc doesn’t change anything.
ACF10, 18 works well.
sorry, please close the ticket, this is just a bad code.
As per the reporter said I close the ticket.