The new Tamron 70-180mm f/2.8 Di III VC VXD G2 lens is now officially released and available for pre-order at:
Shipping will start on October 12. Additional information can be found here:
Tamron announces the development of a new 70-180mm f/2.8 Di III VC VXD G2 lens for Sony E-mount
New Tamron 70-180mm F/2.8 Di III VC VXD G2 lens leaked online