According to AVM it won't replace both, just the HH unfortunately
This accords with some advice that I was reading yesterday. Deutsche Telecom, it would seem, is in the process of rolling out FTTH in some German cities and they are saying to their customers that they will have to move from a DSL modem router to a broadband router with an Ethernet WAN (Internet) port.
The article goes on to say that some high-end modem routers will have a dual-WAN setup which uses an Ethernet port as a secondary WAN port and this may be in the form of a LAN port that can become a WAN port or as a dedicated WAN port.
Finally, I should add that the new beta firmware seems to be a marked improvement on the old firmware. My ADSL2+ connection has now been stable for 13 days with an unusually low error rate. I have left the downstream SNR slider in the mid position which is giving me a target SNR of 5/6 and a downstream connection rate of 16.6Mbps. The WMMAL exchange has gone unusually quiet on the FTTC front. After a flurry of activity just before Christmas, the town is covered with lots of new FTTC cabinets which all seem to have a power supply to them (but not connected), and links fitted, but no sadly fibre installation teams in sight!!