It doesn't run 'boost' again after the very first switch on, it restarts at something like medium output. That's difficult to tell as the motor speed seems to be infinitely variable not in steps. I've never been certain if the glow pin is energised during re-start although I think it must be as the chamber can be totally cooled however I never notice as much voltage dip on the leisure battery as is seen on initial start-up. I must try to find the enthusiasm to monitor it sometime.
The way mine are working is exactly how the Eberspacher installations show, as linked above.
These heaters have come a long way since the BA4 types which were the first type that I worked on! BA-4 Heater — www.type4.org documentation
