IOS/Android AssetBundle Cache Cleanup

Hi All,

I have a question about asset bundle cache cleanup on mobile devices. Our app has been live for a while and the size of the app has been growing since launch (on my IOS device under settings->general->usage->manage storage it now shows as 1.7GB - initial install + content is around 400mb). We have content releases so completely new asset bundles (as well as new versions of existing asset bundles) are being downloaded frequently. I have looked through the Caching. Api and have experimented with setting different values for Caching.maximumAvailableDiskSpace and Caching.expirationDelay in the hopes that I can trigger a cleanup for old "unused" asset bundles. Unfortunately setting maximumAvailableDiskSpace to something like 500MB and/or Caching.expirationDelay to something low like 1 second (for testing) doesn't seem to have any impact.

After experimenting with the caching api I am now even more unclear on its intended use so my question is:

"What is the Unity best practice for maintaining asset bundle cache size on mobile devices and what api should I be using for the implementation"?

Thanks!