When a Blueprint asset is reloaded, we are currently serializing its CachedDependencies list during the discovery of potential referencers. This can lead to incorrectly treating all dependencies as a potential referencer.
This leads to unnecessary recompiles, increasing the reload time, and may result in undefined behavior due to circular reference relationships with the Blueprint asset that's being reloaded. For macro library dependencies, this will also lead to a recompile of any loaded Blueprint that also depends on that library.
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-162108 in the post.