Thanks for getting in touch.
It is true that Wunderlist is no longer allowing new Wunderlist accounts to be created, however, they aren’t officially shutting down until May 6th, 2020.
Momentum will continue to support the Wunderlist integration until they’ve officially shut down. Additionally, we will make a Microsoft Todo integration available before May 6th. 👍
You can learn more about how Wunderlist is handling this situation in the following article:
Thanks again for your message, Nathaniel. We appreciate your feedback!