According to a Skype Frequently Asked Questions (FAQ) page, users won't be able to download the Skype Wi-Fi application after that date. Those who still have Skype Wi-Fi installed after March 31 will no longer be able to find or use hotspots.
Microsoft is advising those with Skype Credit to use it toward calling mobile and landline numbers.
In June 2015, Microsoft officials confirmed the company was working to roll out an updated and rebranded version of Skype Wi-Fi that was called Microsoft Wi-Fi.
I asked Microsoft if the company was still planning to roll out Microsoft Wi-Fi or if it was getting out of the Wi-Fi hotspot access business completely. No word back so far. But the Microsoft Wi-Fi website, which as of earlier today still had a "coming soon" message, is now down.
Microsoft was planning to make Microsoft Wi-Fi a service for both consumers and business customers (in the latter's case, through Office 365 plans). I don't see any reference to Skype or Microsoft Wi-Fi on the company's Office 365 plan pages.