This might help you with the 1st one. The HOLD function uses the REPEAT [Aux to Performance] switch.
Have to think about that one. Kind of a combination of Ducked Delay, DynaVerb, …
Maybe SpaceTime, with an expression pedal.
Thank you. But I’ve tried that one. The feedback isn’t repeating infinitely and it doesn’t feed back at 6 seconds interval. In the other link you provided, there’s someone saying that if you switch over the delay mix the other way the first repeat comes out (back) at 9 seconds. So…I don’t know…is even 9 Seconds delay possible?