On April 28th (Wednesday), Episode 1 to 4 will be available for free starting 12 noon for a limited period of time (exact time not mentioned).
Starting May 7th (Friday), each episode will be up at 12 noon: May 7th - Episode 1, May 14th - Episode 2, May 21st - Episode 3 and May 28th - Episode 4.
The anime will also be available for access on mobile phone.
Information is from SD Gundam Sangokuden Brave Battle Warriors's official site. Image is from this previous posting.