Re-link Multiple Files

In case you don't want to restart everytime you want to change all links to the same file at once, you can run this script, choose the link you want to replace, choose your new file, and it will replace any link sharing that name automatically. 

/**
 * This script replaces all linked files with the same name at one time in Adobe Illustrator.
 * It allows the user to select the link to replace from a list of current links using a drop-down menu
 * and then choose the new file from a dialog.
 */

function replaceAllLinksWithSameName() {
    var doc = app.activeDocument;
    var placedItems = doc.placedItems;
    var linkNames = [];

    // Collect all unique link names
    for (var i = 0; i < placedItems.length; i++) {
        var placedItem = placedItems[i];
        if (placedItem.file) {
            var fileName = placedItem.file.name;

            // Check if the fileName is already in linkNames
            var isUnique = true;
            for (var j = 0; j < linkNames.length; j++) {
                if (linkNames[j] === fileName) {
                    isUnique = false;
                    break;
                }
            }

            if (isUnique) {
                linkNames.push(fileName);
            }
        }
    }

    if (linkNames.length === 0) {
        alert("No linked files found in the document.");
        return;
    }

    // Create a dialog for link selection
    var dialog = new Window("dialog", "Select Link to Replace");
    dialog.orientation = "column";

    var dropdown = dialog.add("dropdownlist", undefined, linkNames);
    dropdown.selection = 0;

    var okButton = dialog.add("button", undefined, "OK");
    okButton.onClick = function() {
        dialog.close(1);
    };

    if (dialog.show() != 1) {
        return;
    }

    var oldFileName = dropdown.selection.text;
    var newFile = File.openDialog("Select the new file to replace " + oldFileName);

    if (newFile) {
        var count = 0;

        for (var k = 0; k < placedItems.length; k++) {
            var placedItem = placedItems[k];
            if (placedItem.file && placedItem.file.name === oldFileName) {
                placedItem.file = newFile;
                count++;
            }
        }

        alert(count + " links have been replaced.");
    } else {
        alert("Operation cancelled or no file selected.");
    }
}

replaceAllLinksWithSameName();

Wait. Hold up, are you saying that if I have 30 files in a folder that is not called "Links" I would have to relink every single one of them manually if the folder name or path changed?  

I have the same issue. We link low res files for proofing purposes and then relink high res when it goes to production. Would LOVE to be able to relink all the files in a document at the same time (without having to go to the linked oubject and select "relink" for every single one.). Would also love it if it put the name of the file in the window when trying to relink. Why is it blank!?