The extension request, if granted, will give you an additional 6 months to either:
(1) use the mark in commerce and file a Statement of Use; or
(2) file another extension request. You can request up to 5 extensions (one every 6 months) from the date the USPTO issued your Notice of Allowance (a temporary, conditional approval of your Intent-To-Use trademark application). To view the date of your Notice of Allowance, visit http://portal.uspto.gov/external/portal/tow and enter your trademark's USPTO serial number.
If the USPTO does not receive a timely extension request or Statement of Use, it will consider your trademark application abandoned.
Please note that all dates are calculated from the date of your Notice of Allowance, not from your original trademark application filing date or any extension.