Originally Posted by AngusMast:
“I won't be doing a full retune. I'll settle for manual retuning each multiplex, but even then the Hitachi HDR5T01 doesn't do it right, I have to delete the channels that are going to change first of all.”

I've got a couple of Vestel T7655s. They are on a slightly earlier software than your Hitachi badged version but after an auto retune they rebuild the timers. Took me totally by surprise the first time as it didn't do it immediately and I only realised when re-entering the 3 timer that all the timers had now been restored.