I am a Spectralayers 12 Pro user, and the email with the offer arrived in my email yesterday. The free trial is for 60 days. I have not tested it myself yet. I do want to evaluate if it’s worth the upgrade before I take the plunge.
Folks in another thread have convinced me to investigate MVSEP for my unmixing needs, and it does seem to be quite a bit better than SL12, so I might be spending some money to buy credits there soon instead of upgrading to SL13.