period of cover is the next consumer's date when the on hand is 0

src/model/flowplan.cpp

@@ -586,18 +586,29 @@ Duration FlowPlan::getPeriodOfCover() const {
 
   // Case 2: Regular case
   left_for_consumption = getOnhand();
-  auto fpiter2 = getBuffer()->getFlowPlans().begin(this);
-  ++fpiter2;
-  while (fpiter2 != getBuffer()->getFlowPlans().end()) {
-    // On hand is 0, we return the next replenishment
-    if (getOnhand() == 0 && fpiter2->getQuantity() > 0.0)
-      return fpiter2->getDate() - getDate();
-    if (fpiter2->getQuantity() < 0.0) {
-      left_for_consumption += fpiter2->getQuantity();
-      if (left_for_consumption < ROUNDING_ERROR)
-        return fpiter2->getDate() - getDate();
+  if (left_for_consumption > 0) {
+    auto fpiter2 = getBuffer()->getFlowPlans().begin(this);
+    ++fpiter2;
+    while (fpiter2 != getBuffer()->getFlowPlans().end()) {
+      if (fpiter2->getQuantity() < 0.0) {
+        left_for_consumption += fpiter2->getQuantity();
+        if (left_for_consumption < ROUNDING_ERROR)
+          return fpiter2->getDate() - getDate();
+      }
+      ++fpiter2;
     }
+  } else {
+    // Case 3:
+    // On hand is 0 so we display the next consumer's date
+    auto fpiter2 = getBuffer()->getFlowPlans().begin(this);
     ++fpiter2;
+    while (fpiter2 != getBuffer()->getFlowPlans().end()) {
+      if (fpiter2->getQuantity() < 0.0) {
+        return max(0L, fpiter2->getDate() - getDate() -
+                           fpiter2->getOperationPlan()->getDelay());
+      }
+      ++fpiter2;
+    }
   }
 
   return Duration(999L * 86400L);