Laravel, Redis, Node.js and Websockets (pubsub?)

We have an API built on Laravel, and we are hoping to add a Redis and Node layer to make it real time compatible, I have a few questions however.

1. A user/client needs to be subscribe to a channel to see any updates, correct?

2. All the examples of this method show the channel being hard coded into the node script, obviously are application needs more than 1 channel, of the top of my head, we will need,

3. User specific notification

4. Project
5. Project Users

My understanding is that if a user subscribes to a channel called 'project' that manages to updates of a project, then if a project name is changed then all projects will be changed to that name? Maybe I wrong.

Any way here is my node script

    var https = require('https'),       // module for https
    fs =    require('fs'),         // required to read certs and keys
    express = require('express');

var options = {
    key:    fs.readFileSync('ssl/ssl.app.dev.key'),
    cert:   fs.readFileSync('ssl/ssl.app.dev.crt'),
    requestCert:        true,
    rejectUnauthorized: false
};

var app = express();

var server = https.createServer(options, app);

const redis = require('redis');
const io = require('socket.io');
const client = redis.createClient();

server.listen(3000, 'localhost');

io.listen(server).on('connection', function(client) {
    const redisClient = redis.createClient();
    var channel;
    //console.log(redisClient);
    redisClient.subscribe('project_id_64');


    redisClient.on("message", function(channel, message) {
        //Channel is e.g 'score.update'
        console.log("Channel: " + channel);
        console.log("Message: " + message);
        client.emit(channel, message);
    });

    client.on('disconnect', function() {
        redisClient.quit();
    });
});

As you can see I subscribe to redis through a string, is there a way to make this so I can subscribe to redis through variable that can change?