I have been advised by both Bose in a shop and technical support the following:
"To rebroadcast audio from a record player around the house you would need to connect the amp or turntable directly to the Soundtouch Wireless Link Adapter's auxiliary input. Then you could have other SoundTouch speakers around the house able to be streamed to. Please be advised that the auxiliary rebroadcasting feature is currently only in beta; i.e. in testing, and is not a fully fledged feature as yet."
Has anybody manged to do this personally. (I had previously tried a blue tooth record player and thought it was totally rubbish !)