The IRS doesn't start processing returns officially until January 28. Every January there are a few returns they pull early for testing, and it sounds like that is what happened to you, and thus your early acceptance. It's possible they won't do any more processing on your return until they officially open, or they may test it periodically before then. So you may see it come and go with that tool.
Perhaps that message came up because it's not actively processing at the moment. I wouldn't worry about unless it continues to not give you info after they officially open on January 28.
If you want to double-check that your return was indeed accepted, sign into your account and look at the return status, or you can check with this tool:
https://shop.turbotax.intuit.com/efile/efile_status_lookup.jsp
