Dpreview posted their press text ahead of the official announcement:

Sony has announced the FE 20-70mm F4 G, a standard zoom that extends out to the ultra-wide region while maintaining its reach at the long end. The unstabilized lens offers a constant F4 aperture in a relatively compact and lightweight body.

The 20mm starting point gives an additional ten degrees of diagonal angle-of-view compared to 24mm (for reference, the difference between 28 and 24 is around eight degrees). Sony points out that this means you can still maintain a wide angle of view even with the additional crop applied by engaging digital stabilization in video.

We found the combination of standard range with extension out to the ultra-wide valuable for both stills and video when we used Panasonic’s Lumix 20-60mm F3.5-5.6, and the addition of more reach at the long end only expands that flexibility.

The lens has a dedicated aperture ring, as well as zoom and focus rings. The aperture ring has a lock switch to keep in in (or out of) its ‘A’ setting, that passes aperture control to the camera body. There’s also a switch on the opposite side of the body that de-clicks the aperture ring, allowing smooth changes when shooting video.

The FE 20-70mm F4 G uses twin ‘XD’ linear motors, with Sony claiming its focus is 60% faster than the FE 24-70mm F4 ZA, whose focus is driven by a similar technology.

It offers a minimum focus distance of 0.25m (9.8″) in manual focus mode, and delivers a maximum magnification of 0.39x, at the 70mm end of the zoom.

The lens weighs 488g ( including the supplied hood), is 78.7mm (3.1″) wide and 99mm (3.9″), extending to around 139mm (5.5″) when fully zoomed-in. It has a 72mm front filter thread. As you might expect for a modern zoom that covers the ultra-wide range, it requires digital correction as part of its design.

The Sony FE 20-70mm F4 G will be available around the start of February at a recommended price of $1099.