I had the same issue after using the AVM rescue utility. There is a variable in the bootloader which specifies which ip address the EVA bootloader should listen on. After EVA it will run the regular firmware and listen at 192.168.178.1 while refusing any connection on the ftp port.
The key to this is a magic UDP packet sent by your PC which also the AVM rescue utility uses to modify this variable containing the address EVA should listen on.
This can be done using a script which is available as
Windows Powershell ( https://github.com/PeterPawn/YourFritz/blob/master/eva_tools/EVA-Discover.ps1 , be sure to use "set-ExecutionPolicy unrestricted" or Windows will complain)
Linux Shell ( https://github.com/PeterPawn/YourFritz/blob/master/eva_tools/eva_discover )
The "TO" ip address you should pass to the script will be the one EVA listens on.