I'm always fishing stuff out the back of the freezer that i'd forgotten about, and I have no idea how long it's been there. As with any food you just need to use your senses: sight, smell and common. As long as it looks and smells OK and if frozen you defrost it thoroughly and ensure it is cooked right through then there should'nt be any problem. I rarely take any notice of dates especially as on more than one occasion when I used to buy supermarket well in date 'fresh' chicken i have unwrapped it and it's nearly knocked me backwards with the stink. Just because it still had 4 or 5 days on it didn't meant it was OK to eat, it was rank and it went straight in the bin.