Hi Rachel,
I think you can customize this part in Website & Registration > Language Management. In the search box above the Custom Text column, type in "your registration has been confirmed" (no quotes) and then hit Enter. There should only be one option that comes up. In the Action column on the far left of that option, click on the pencil icon. This will open a Custom Text box where you can enter your own message. Save the changes by clicking on the disk icon in the Action column, and then go through your testing to make sure the message appears how you want it to.
Hope this helps!
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Sarah Speed
Administration Systems Coordinator
Ottawa Bluesfest
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