That is a Best Guess Estimate date. It could be the anticipated internal release date after which they have to make CD/DVD masters and then upload the mastered data to the website for customer download. Like Bob said, it could be days or weeks before it is actually available.
PTC Proprietary: For Use by PTC Customers for Planning Purpose Only (Forecasted Dates May Change without Notice)
The following information is furnished for informational use only, is subject to change without notice, and should not be construed as a guarantee, commitment, condition, or offer by PTC. The release date of final production versions of PTC products may be revised frequently; accordingly, you should not rely on this data for production or purchasing decisions.