Won't be a replacement or support for the 'My Humminbird' feature, but you can still go to Humminbird.com home page and cursor to the 'SUPPORT' title. Slide down to 'Software Updates' and click on it. It'll open to 'Fish Finders' where you scroll down to your 'Series' such as Helix, 1100, 900, etc. Click on the series, scroll down until you find your model and click on it.
Also, re-registering isn't necessary if you've previously done so and had the 'My Humminbird.' The customer service rep I spoke with told me that although their section doesn't have access to that data, it's still stored someplace on their servers and available to their technicians for warranty purposes, etc. The 'Sign-In' option is for persons who have an actual account because they purchased HB products directly.