I was there yesterday. I heard all Frozen Fun will be shutting down May 15th because they need a week do redo the section for the 60th anniversary starting May 22nd.
Based on everything that has been reported since Frozen Fun started, different activities have different end dates or no end date at all.
April 30: Olaf's Snow Fest
May 13 or 15: Frozen Fun (Sing-A-Long at Muppet Theater, Freeze the Night)
No announced end date:
Anna & Elsa Meet & Greet
Wanna Draw a Snowman (Animation Academy)
Frozen at Fantasy Faire (Royal Theatre)
Anna & Elsa Pre-Parade Float (Soundsational)
Permanent (or not likely to be removed in the near future):
Arandelle in Storybook Canal
Anna & Elsa Boutique in DTD
Frozen will be long go by the time we arrive? Best news I've heard all week!
The concentration of Frozen in Hollywoodland in DCA will likely be gone by the start of the 60th anniversary, but there will still be plenty of Frozen scattered throughout the parks. Unless you wait until Frozen is no longer popular, you're going to see a large Frozen presence in the park anyway.