Matt,
First the payment needs to be stopped with the bank if not taken already.
You cannot submit the application for 30 days after withdrawal. I guess in the Email you should ask them to return the Original Life in UK test transcript.
Here is what the home office website says;
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Withdrawing your application
Should you no longer wish to proceed with your application you may ask us to withdraw and return all your documents. You will no longer have the option to re-submit your application within 30 days if you choose to withdraw your application. Any subsequent applications made will therefore enter the queue at the date of submission to the Home Office.
Important information for all applicants who are requesting urgent consideration or withdrawing an application
You should not make travel plans after you have made your application and submitted your travel documents, as we can not guarantee that we will be able to return documents by a specific date.
If you need to ask us to your application or withdraw urgently, please e-mail your request, to
BaRCUrgentReturns@UKBA.gsi.gov.uk. Due to the high volume of requests we receive we cannot individually acknowledge your request, and will only fast-track your application in the exceptional circumstances detailed above.
Best Rgds
vr
