Your Utility Patent Application will obtain no benefit from the earlier filing date of your Provisional Application unless the Utility Patent Application properly references the Provisional Application and claims the benefit of its filing date.
Your Utility Patent Application can reference and claim the benefit of the filing dates of several Provisional Applications, so long as the Provisional Applications all were filed within one year of the filing date of the Utility Patent Application, and so long as the Utility Patent Application properly references the Provisional Applications and claims filing date benefits.
You have one opportunity which is available only when your Utility Application is filed to avoid being charged a costly Publication Fee by the USPTO, and you exercise this option by filing a properly worded Non-Publication Request and Certification at precisely the time when your Utility Patent Application is being filed in the USPTO. Consult your patent attorney, for there are some drawbacks and conditions attendant the filing of a Non-Publication Request, and not all applicants are entitled to request Non-Publication.
Utility Patent Applications that reference and claim the benefit of the filing date of one or more earlier-filed Provisional Applications move through their time of pendency in the USPTO at the same speed as Utility Patent Applications that reference no earlier-filed Provisional Applications.
If the USPTO determines that you are entitled to receive a Utility Patent, you will still need to pay an Issue Fee to obtain your Utility Patent; and, after you have your Utility Patent in hand, there will be maintenance fees to pay at 3.5, 7.5 and 11.5 years after the issue date of your Utility Patent to keep your Utility Patent in force.