Wifi driver for RTL8191SU

I have a USB wifi adapter based on the subject chipset.  Debian Linux
for its new release (9.x) incorporates version 4.9 of the kernel, which
does not work with the existing driver for this USB wifi adapter.  The
driver for it (under Debian 8.x) shows as "r8712U".  There's a movement
afoot to update the driver.

Any idea when an updated driver (or a wide beta restoring *some*
functionality) could be expected?