How do you read the manufacture date on the Conti GP4000s?

I just purchased a set online and before I put them on my bike, I want to check the manufacture date.

I searched the website, around the internet and emailed Continental through their website. Didn't find anything and have not heard back from them.

This is what I found the tires:

23-622 C 210

E4 (w/a circle around the E4) 88 R -

208850

Any info is appreciated!
dt