Why LoadFromCacheOrDownload only accepted network online environment?

Hello. My project using assetbundles 90% of total resources(grand total on project) over 300mb
de-compressed all files,
When was a start line of project (about 10 months before), Is LoadFromCacheOrDownload function
stabilize and trust enough to commercial program? or not? very think with research about those several weeks, and conclusion then decided using one.
(Or using natively WWW with customized programming Caching issues, Versioning Issues…)
These day qualify assurance test and test I realized that function very positive commercial functions
as automatic versioning, automatic caching with nice stabilization,
Only except one Issue that is It’s absolute not working on offline network even all assetbundles were already cached to clients device disks.
Official documents not mentioned about that but function name sounds like a
first if assetbundles already exists on Cache, load from Cache, or not download assetbundle from url.

So I wonder about that if already downloaded exists on Cache, Is online networks necessity?
This wonder cause of my projects are using TCP socket (if disconnected try to reconnection to socket server)
not the using web socket so all functions based on online networks.
My questions are 3.

  1. Can I know exactly full path of downloaded each assetbundles on cache based on
    using LoadFromCacheOrDownload ?

  2. Why LoadFromCacheOrDownload function need network’s online guarantee even if
    assetbundles were already cached?

  3. Is there any substitute LoadFromCacheOrDownload function not using customized WWW?

Thank to replies.

Solved. LoadFromCacheOrDownload working well.