Multiple Entity Reference creation using Services and Autocomplete Widget

Question

This is in reference to: Entity Reference create problem with REST server using Services and How to use Services to create new node with Entity Reference field?

What if I want to create multiple entity references in a certain field with widget type Autocomplete (not Autocomplete with tagging)?

for example, this doesn't work and results in only the 1st reference being added, not the 2nd reference:

"field_nodes_list": {
    "und": [
        {
            "target_id": "Title (8756)"
        },
        {
            "target_id": "Description (12983)"
        }
    ]
}

I tried using Autocomplete tags style by doing the below, which works, but only if the field is less than 1024 characters. I want to use the non-tag Autocomplete method above to do the same thing:

"field_nodes_list": {
    "und": "Title (8756), Description (12983)"
}