Hi anumtahir,
Thanks for getting back to us here for additional information. One of the many great things that QuickBooks Online has to offer, is the ability to access your account for a full year, after cancelling your subscription. If you need an extension, you'll just want to log into your account and re-subscribe before the cancellation date reaches the deadline. The subscription fee is prorated, so you'll be charged for the first month. This will activate the account so you can add or edit any data, as you see necessary. Follow the steps to cancel again, so you have another year to access your company, from the date of cancellation.
Please don't hesitate to ask other questions. We're always glad to assist!
