Can I then use the previous work from the trial into the subscribe/buy?

Abriel,

I have mentioned this intriguing inquiry to an Adobe friend with a deep knowledge of such matters.

This is interesting. Most people do not notice this about the free trial. The free trial is not of course intended for this purpose. Free trials are much abused, but what applies is the EULA. We cannot give you permission to ignore this EULA, you must make your own moral and legal decision. Are you are person who hopes to make a living from creating things, and do you expect/wish that other people respect your intellectual property and any rules/limitations you put on it? You might consider this point when you decide whether to respect Adobe's intellectual property.