If you are emailing your list consistently, they will likely receive your welcome sequence AND broadcast messages.
To keep things simple, we would suggest to not worry about this for now. Don’t worry if your prospects are receiving your welcome sequence and broadcast messages at the same time.
It shows you are email consistently and are keeping them in mind. As you get more advanced and start sending more emails, autoresponders such as Aweber and ConvertKit allow you to add advanced automation to avoid this.
But if you’re starting, please don’t worry about this.