diff --git a/opm/simulators/flow/FlowGenericProblem.hpp b/opm/simulators/flow/FlowGenericProblem.hpp
index 2531cd6b2..5d106cd4a 100644
--- a/opm/simulators/flow/FlowGenericProblem.hpp
+++ b/opm/simulators/flow/FlowGenericProblem.hpp
@@ -308,7 +308,8 @@ protected:
     bool shouldWriteRestartFile() const
     { return false; }
 
-    bool beginEpisode_(bool enableExperiments,
+    bool beginEpisode_(std::size_t numDof,
+                       bool enableExperiments,
                        int episodeIdx);
     void beginTimeStep_(bool enableExperiments,
                         int episodeIdx,
diff --git a/opm/simulators/flow/FlowGenericProblem_impl.hpp b/opm/simulators/flow/FlowGenericProblem_impl.hpp
index 7c0fa2ed1..f78a668e0 100644
--- a/opm/simulators/flow/FlowGenericProblem_impl.hpp
+++ b/opm/simulators/flow/FlowGenericProblem_impl.hpp
@@ -418,7 +418,8 @@ vapparsActive(int episodeIdx) const
 
 template<class GridView, class FluidSystem>
 bool FlowGenericProblem<GridView,FluidSystem>::
-beginEpisode_(bool enableExperiments,
+beginEpisode_(std::size_t numDof,
+              bool enableExperiments,
               int episodeIdx)
 {
     if (enableExperiments && gridView_.comm().rank() == 0 && episodeIdx >= 0) {
@@ -438,6 +439,10 @@ beginEpisode_(bool enableExperiments,
         OpmLog::info(ss.str());
     }
 
+    this->mixControls_.init(numDof,
+                        episodeIdx,
+                        eclState_.runspec().tabdims().getNumPVTTables());
+
     const auto& events = schedule_[episodeIdx].events();
 
     // react to TUNING changes
diff --git a/opm/simulators/flow/FlowProblem.hpp b/opm/simulators/flow/FlowProblem.hpp
index 79939dff3..86fe9857f 100644
--- a/opm/simulators/flow/FlowProblem.hpp
+++ b/opm/simulators/flow/FlowProblem.hpp
@@ -545,7 +545,7 @@ public:
             this->model().linearizer().updateDiscretizationParameters();
         }
 
-        bool tuningEvent = this->beginEpisode_(enableExperiments, this->episodeIndex());
+        bool tuningEvent = this->beginEpisode_(this->model().numGridDof(), enableExperiments, this->episodeIndex());
 
         // set up the wells for the next episode.
         wellModel_.beginEpisode();
diff --git a/opm/simulators/flow/MixingRateControls.cpp b/opm/simulators/flow/MixingRateControls.cpp
index b8ea2bab2..11ce8799f 100644
--- a/opm/simulators/flow/MixingRateControls.cpp
+++ b/opm/simulators/flow/MixingRateControls.cpp
@@ -97,20 +97,19 @@ template<class FluidSystem>
 void MixingRateControls<FluidSystem>::
 init(std::size_t numDof, int episodeIdx, const unsigned ntpvt)
 {
-    // deal with DRSDT
-    //TODO We may want to only allocate these properties only if active.
-    //But since they may be activated at later time we need some more
-    //intrastructure to handle it
-
-        maxDRv_.resize(ntpvt, 1e30);
-        lastRv_.resize(numDof, 0.0);
+    // allocate DRSDT related vectors
+    if (this->drsdtActive(episodeIdx) && maxDRs_.empty()) {
         maxDRs_.resize(ntpvt, 1e30);
         dRsDtOnlyFreeGas_.resize(ntpvt, false);
         lastRs_.resize(numDof, 0.0);
+    }
+    if (this->drvdtActive(episodeIdx && maxDRv_.empty())) {
+        lastRv_.resize(numDof, 0.0);
         maxDRv_.resize(ntpvt, 1e30);
-        if (this->drsdtConvective(episodeIdx)) {
-            convectiveDrs_.resize(numDof, 1.0);
-        }
+    }
+    if (this->drsdtConvective(episodeIdx) && convectiveDrs_.empty()) {
+        convectiveDrs_.resize(numDof, 1.0);
+    }
 }
 
 template<class FluidSystem>
@@ -170,14 +169,14 @@ updateExplicitQuantities(const int episodeIdx,
     const auto& oilVaporizationControl = schedule_[episodeIdx].oilvap();
     // DRSDT is enabled
     for (std::size_t pvtRegionIdx = 0; pvtRegionIdx < maxDRs_.size(); ++pvtRegionIdx) {
-        if (this->drsdtActive(episodeIdx, pvtRegionIdx)) {
+        if (oilVaporizationControl.drsdtActive(pvtRegionIdx)) {
             maxDRs_[pvtRegionIdx] = oilVaporizationControl.getMaxDRSDT(pvtRegionIdx) * timeStepSize;
         }
     }
 
     // DRVDT is enabled
     for (std::size_t pvtRegionIdx = 0; pvtRegionIdx < maxDRv_.size(); ++pvtRegionIdx) {
-        if (this->drvdtActive(episodeIdx, pvtRegionIdx)) {
+        if (oilVaporizationControl.drvdtActive(pvtRegionIdx)) {
             maxDRv_[pvtRegionIdx] = oilVaporizationControl.getMaxDRVDT(pvtRegionIdx) * timeStepSize;
         }
     }
@@ -249,7 +248,7 @@ maxGasDissolutionFactor(const unsigned timeIdx,
                         const int episodeIdx,
                         const int pvtRegionIdx) const
 {
-    if (!this->drsdtActive(episodeIdx, pvtRegionIdx) || maxDRs_[pvtRegionIdx] < 0.0) {
+    if (!this->drsdtActive(episodeIdx, pvtRegionIdx)) {
         return std::numeric_limits<Scalar>::max() / 2.0;
     }
 
@@ -275,7 +274,7 @@ maxOilVaporizationFactor(const unsigned timeIdx,
                          const int episodeIdx,
                          const int pvtRegionIdx) const
 {
-    if (!this->drvdtActive(episodeIdx, pvtRegionIdx) || maxDRv_[pvtRegionIdx] < 0.0) {
+    if (!this->drvdtActive(episodeIdx, pvtRegionIdx)) {
         return std::numeric_limits<Scalar>::max() / 2.0;
     }