The old QuickBooks XML SDK online integration in Flex will be expiring in just over a week on Tuesday, Sept. 23, 2014. If you are not sure which integration that is or if you are using it, it is the one where you had to manually paste in a connection ticket from QB Online into the Financials > Accounting Integration > QuickBooks settings tab area in order to connect. This is happening due to Intuit (the QB company) retiring the service for good. See the Intuit post about this here: https://developer.intuit.com/blog/2014/09/05/final-migration-update-quickbooks-online-sdk-to-quickbooks-online-rest-api-v3. Flex will continue to contain the integration code past the deadline but it will be useless due to the Intuit cutoff. Subsequently in the next few months we will rip out the old integration code and we will be solely using the new integration for QB Online.
According to our tracking data, we still have a few customers who are using the integration, however it is tricky to know exactly who is using it. If you have not switched over yet, I recommend that you do so in the next day or two. I have another blog post here http://flexrs.wpengine.com/new-quickbooks-online-integration-is-here/ that describes how to connect and get going.
If you have any questions or concerns about this, please contact firstname.lastname@example.org. Happy Integrating!