After alot of messing around trying to locate the cause for loss of power and hesitation under acceleration, I have finally solved the mystery. This is on an AUM engine which is identical to the AUQ (180bhp), so not sure if it will apply to LCRs. Having repaired and re-fitted the hose and driven it for a couple of days, the hesitation has gone, full power has returned and the fuel consumption is alot better according to the the MFI.
The rubber hose has rotted due to oil and ruptured under boost. This hose will see full boost pressure.
This is the location of the hose, please note the hose is not fitted in this photo.
My repair using puncture repair kit and tie wraps.