Maybe you will be able to physically enter the Samaria gorge, but as long as it is not officially opened, entrance is prohibited. And usually that is for a good reason.
The gorge will be unsafe, maybe due to a high water level or damage to the path. It all depends on the actual weather at that time, and the damage to the gorge from the past winter period.
See this message on the old forum about last year: http://www.sfakia-crete-forum.com/read.php?3,2413
If there is little damage to the gorge, specially the entrance from down, from Agia Roumeli, might open before the 1st of May, as it did in 2014:
The Forest Directorate of Chania announced the opening of the National Park of Samaria from the south entrance (Agia Roumeli) for the first two kilometers, on Saturday 12 April 2014, and throughout the full length of the central path (Xiloskalo - Agia Roumeli ) from Monday 21 April, 2014, after a decision by the Secretary General of the Decentralized Administration of Crete.
Keep an eye on this forum, as I will post any news about the opening of the gorge here.
All the best,