The units purchased will need to be used by 12/31. Any unused units will be lost. Your eSignature purchase is not refundable or transferable and may not be carried to another tax year.  Therefore, do not purchase more than you need to use for this tax season.

If so, yes.. I think it should say this:

The units purchased will need to be used by 12/31. Any unused units will be lost. Your eSignature purchase is not refundable or transferable and may not be carried to another tax calendar year.  Therefore, do not purchase more than you need to use for this tax calendar year. Also note, you can use any eSignatures you purchase in prior versions that still support eFile.