Is my Flock Block expired?

[lovenati]

My flock block has been around for about 4 months...I broke it into pieces so they could get to the seeds...but I'm afraid it's expired. They are very picky eaters so I tend to think if it were bad they wouldn't eat it. Thoughts?

 

[GitaBooks]

I'm not sure if its safe after all this time. Vitamins can break down and fungus or mold may grow up. Is it kept dry?