Why is information on hard drive compatibility so scarce on the WDC website? I even tried a chat conversation, but despite attempting to “talk to Jimmy” I got no response to my question after 5 minutes so gave up waiting. 
I’ve had a PR2100 for 5 or 6 years now, and it has a pair of 8TB drives in it. I’m running out of space so looking to put a couple of 12TB drives in to replace them.
How do I know if the PR2100 will recognise a 12TB size drive? The ‘product overview’ PDF only mentions 0TB/4TB/8TB/12TB/16TB/20TB total capacities. This is probably because 10TB was the maximum size drive when the product was released, but does anybody at WDC ever think of updating this information? I don’t want to just cross my fingers and assume it will work.
Have firmware updates (I’m also now running OS5) facilitated the use of larger capacity drives? I can see I can configure a purchase of a PR2100 with a 28TB capacity, but not a 24TB capacity. Is this just an oddity, or are 2x 12TB drives genuinely not supported?
It’s this glaring lack of information from Western Digital that makes things far more difficult than things need to be. Nobody wants to spend nearly £500 on a pair of hard drives only to find they are incompatible and then try and arrange a refund!!!
If anybody is running a PR2100/PR4100 with 12TB drives, that are properly being recognised, can they please tell me?
