TRKFT3 Digitizer: compensate for the shift of the reference BC when mCollisionTimeWrtROF < 0

Author: atriolo

Detectors/Upgrades/ALICE3/TRKFT3/common/simulation/src/Digitizer.cxx

@@ -161,7 +161,9 @@ void Digitizer<DetID>::setEventTime(const o2::InteractionTimeRecord& irt, int la
   auto nbc = mEventTime.differenceInBC(mIRFirstSampledTF);
 
   if (mCollisionTimeWrtROF < 0 && nbc > 0) {
+    // move to the ROF it actually belongs to and account this in the time offset wrt updated reference BC
     nbc--;
+    mCollisionTimeWrtROF += o2::constants::lhc::LHCBunchSpacingNS;
   }
 
   mROFsWrtFirstRO = std::floor(float(nbc) / mParams.getROFrameLengthInBC(layer));