Hi,
sorry can't reproduce it. ETA shows me times to be expected.
Sorry, it was my fault. I forgot to change the ETA calculation (on mean speed instead of on the track).
Use this website 'https://mapy.cz' (worldwide and no login required) or apps (mapy.cz for Android and iOS) to make a route; then export it by TwoNav Link from smartphone to Cross+ (or any other TwoNav device) and see that ETE=0, ETA=actual time.
Most probably it is a matter of current the 'mapy.cz' fault.