There are a few different flavours of physics you can use for DAS, and they 'use up' different areas of the spectrum. As long as what you want to do for telecom

There are a few different flavours of physics you can use for DAS, and they 'use up' different areas of the spectrum. As long as what you want to do for telecoms is using completely separate wavelengths (channels or bands) then yes you can do both. Most DAS providers and users prefer to just use un-used/dark fibres though as it avoids any headaches.