Dear Helga, Chris hope your both keeping well 
This forum needs a sticky to explain the differences in cost, availability, size and type of Halion orchestras plus the upgrasdability one fro the other
this is my take on things
1] Halion Sonic version is 16bit
2] Full Halion Symphonic orchestra is 24 bit and not available
3] There is an upgrade path to Halion Symphonic orchestra 16 bit from the C6 free trial, but possibly not to the proper Halion Symphonic
4] Only HSO 16 bit is note expression capable by virtue of being a Sonic SE instrument
5] Halion Syphony orchestra free trial with Cubase 5 is not compatible with note expression.
Please can we have proper info as a sticky