When making cultured milk, right clicking with a milking bucket doesn't do anything - but right clicking with a regular bucket returns a regular bucket of whey, and milking buckets of cultured milk.
Similarly, when adding milk to a mixing vat, it returns a regular minecraft bucket as opposed to an empty GC milking bucket.
Also, taking rennet from a brew kettle with a milking bucket returns a regular bucket.
To replicate:
Set up brew kettle, fill with water + thistle to make rennet; right click the side of the kettle with a milking bucket.
Set up Mixing Vat. Fill with GC milk buckets (note this returns regular buckets). Fill with bucket of rennet, add culture, stir with stick.
Attempt to take Whey/Cultured Milk from Vat with empty milking bucket, then regular buckets
When making cultured milk, right clicking with a milking bucket doesn't do anything - but right clicking with a regular bucket returns a regular bucket of whey, and milking buckets of cultured milk.
Similarly, when adding milk to a mixing vat, it returns a regular minecraft bucket as opposed to an empty GC milking bucket.
Also, taking rennet from a brew kettle with a milking bucket returns a regular bucket.
To replicate: Set up brew kettle, fill with water + thistle to make rennet; right click the side of the kettle with a milking bucket. Set up Mixing Vat. Fill with GC milk buckets (note this returns regular buckets). Fill with bucket of rennet, add culture, stir with stick. Attempt to take Whey/Cultured Milk from Vat with empty milking bucket, then regular buckets