Dear Bob O: First off, all the streamers are now accepting the high res (e.g. 2496) master. So it’s the one and only master that has to be shipped out. Apple will use the 2496 (converted from wav to ALAC for streaming) and stream the ALAC in their lossless service. Apple will downsample the 2496 to 3248 for their lossy service and convert from 3248 to AAC. So far, no dithering was involved nor necessary! Nor was noise shaped dither since we sent the high res to Apple!
Spotify will take the 2496 and downsample it to 3248, then codec it to their lossy format. So again, only floating point was involved, no additional dithering, just encoding.
On the other hand, if your client uses CD Baby, they will force you to send them 1644 for all the regular services. CD Baby is the devil there, and we mastering engineers are telling our clients to use another service until CD Baby gets their high res act together. Regardless, let’s see what happens with CD Baby. If the 1644 master was produced with noise shaping. In the case of Apple, it will go into their lossy stream and be encoded DIRECTLY to AAC from the 1644 master. The noise shaping will have no adverse effect on Apples 256 kbps codec. Same with Spotify.
So I think you’re worried about a non-problem problem.