Do not be concerned they have accepted the form as demonstrated by your receipt of the biometrics notice. If the form was not acceptable they would have rejected it when it was received. Good luck on your exam.
The answer provided here is general in nature and does not take into account other factors that may need to be reviewed for a more precise answer. You should consult with an immigration attorney before taking any action. The answer here is not intended to create an attorney-client relationship.
You filed before May 1 ... you will be fine.
PROFESSOR OF IMMIGRATION LAW for over 10 years -- This blog posting is offered for informational purposes only. It does not constitute an attorney-client relationship. Also, keep in mind that this is an INTERNET BLOG. You should not rely on anything you read here to make decisions which impact on your life. Meet with an attorney, via Skype, or in person, to obtain competent personal and professional guidance.
I would not be concerned. You fied before May 1 and you received a reciept notice. If Immigration wanted the new version they would have rejected your filing or they could always ask you to submit an update version. None of that has happened so i would just await the process.