diff --git a/src/FwdState.cc b/src/FwdState.cc
index bbca57e56f6..83bd07b31d4 100644
--- a/src/FwdState.cc
+++ b/src/FwdState.cc
@@ -580,7 +580,12 @@ FwdState::markStoredReplyAsWhole(const char * const whyWeAreSure)
     if (EBIT_TEST(entry->flags, ENTRY_ABORTED))
         return;
 
-    storedWholeReply_ = whyWeAreSure;
+    if (!storedWholeReply_) {
+        storedWholeReply_ = whyWeAreSure;
+
+        if (!reforward())
+            entry->completeSuccessfully(whyWeAreSure);
+    }
 }
 
 void
@@ -1314,7 +1319,11 @@ FwdState::reforward()
         return 0;
     }
 
-    assert(e->store_status == STORE_PENDING);
+    if (e->store_status == STORE_OK) {
+        debugs(17, 3, "No, the entry is STORE_OK already");
+        return 0;
+    }
+
     assert(e->mem_obj);
 #if URL_CHECKSUM_DEBUG
 
diff --git a/src/clients/FtpClient.cc b/src/clients/FtpClient.cc
index 15a20b4b10c..7a48812a003 100644
--- a/src/clients/FtpClient.cc
+++ b/src/clients/FtpClient.cc
@@ -179,6 +179,14 @@ Ftp::DataChannel::addr(const Ip::Address &import)
     port = import.port();
 }
 
+void
+Ftp::DataChannel::appended(const size_t size)
+{
+    readBuf->appended(size);
+    payloadSeen += size;
+    debugs(9, 5, size << " bytes to readBuf, payloadSeen: " << payloadSeen);
+}
+
 /* Ftp::Client */
 
 Ftp::Client::Client(FwdState *fwdState):
@@ -979,8 +987,7 @@ Ftp::Client::dataRead(const CommIoCbParams &io)
     }
 
     if (io.flag == Comm::OK && io.size > 0) {
-        debugs(9, 5, "appended " << io.size << " bytes to readBuf");
-        data.readBuf->appended(io.size);
+        data.appended(io.size);
 #if USE_DELAY_POOLS
         DelayId delayId = entry->mem_obj->mostBytesAllowed();
         delayId.bytesIn(io.size);
diff --git a/src/clients/FtpClient.h b/src/clients/FtpClient.h
index a42e0e199a6..9e1d4614f33 100644
--- a/src/clients/FtpClient.h
+++ b/src/clients/FtpClient.h
@@ -99,11 +99,17 @@ class DataChannel: public Ftp::Channel
 
     void addr(const Ip::Address &addr); ///< import host and port
 
+    /// updates counters after this number of bytes have been added to readBuf
+    void appended(size_t size);
+
 public:
     MemBuf *readBuf;
     char *host;
     unsigned short port;
     bool read_pending;
+
+    /// amount of message payload/body received so far
+    uint64_t payloadSeen = 0;
 };
 
 /// FTP client functionality shared among FTP Gateway and Relay clients.
diff --git a/src/clients/FtpGateway.cc b/src/clients/FtpGateway.cc
index 675c08dfec2..c2bc3a0bbca 100644
--- a/src/clients/FtpGateway.cc
+++ b/src/clients/FtpGateway.cc
@@ -970,8 +970,10 @@ Ftp::Gateway::processReplyBody()
         return;
     }
 
+    const auto availableDataSize = data.readBuf->contentSize();
+
     /* Directory listings are special. They write ther own headers via the error objects */
-    if (!flags.http_header_sent && data.readBuf->contentSize() >= 0 && !flags.isdir)
+    if (!flags.http_header_sent && !flags.isdir)
         appendSuccessHeader();
 
     if (EBIT_TEST(entry->flags, ENTRY_ABORTED)) {
@@ -1000,14 +1002,17 @@ Ftp::Gateway::processReplyBody()
         parseListing();
         maybeReadVirginBody();
         return;
-    } else if (const auto csize = data.readBuf->contentSize()) {
-        writeReplyBody(data.readBuf->content(), csize);
-        debugs(9, 5, "consuming " << csize << " bytes of readBuf");
-        data.readBuf->consume(csize);
+    } else if (availableDataSize) {
+        writeReplyBody(data.readBuf->content(), availableDataSize);
+        debugs(9, 5, "consuming " << availableDataSize << " bytes of readBuf");
+        data.readBuf->consume(availableDataSize);
     }
 
     entry->flush();
 
+    if (availableDataSize && theSize >= 0 && data.payloadSeen >= static_cast<uint64_t>(theSize))
+        markParsedVirginReplyAsWhole("whole virgin body");
+
     maybeReadVirginBody();
 }
 
@@ -1151,6 +1156,7 @@ Ftp::Gateway::start()
         SBuf realm(ftpRealm()); // local copy so SBuf will not disappear too early
         const auto reply = ftpAuthRequired(request.getRaw(), realm, fwd->al);
         entry->replaceHttpReply(reply);
+        fwd->markStoredReplyAsWhole("checkAuth failed");
         serverComplete();
         return;
     }
@@ -1257,6 +1263,7 @@ Ftp::Gateway::loginFailed()
 
     // add it to the store entry for response....
     entry->replaceHttpReply(newrep);
+    fwd->markStoredReplyAsWhole("loginFailed");
     serverComplete();
 }
 
@@ -2225,6 +2232,7 @@ Ftp::Gateway::completedListing()
     ctrl.message = nullptr;
     entry->replaceHttpReply(ferr.BuildHttpReply());
     entry->flush();
+    fwd->markStoredReplyAsWhole("completedListing");
     entry->unlock("Ftp::Gateway");
 }
 
@@ -2239,8 +2247,9 @@ ftpReadTransferDone(Ftp::Gateway * ftpState)
         if (ftpState->flags.listing) {
             ftpState->completedListing();
             /* QUIT operation handles sending the reply to client */
+        } else {
+            ftpState->markParsedVirginReplyAsWhole("ftpReadTransferDone code 226 or 250");
         }
-        ftpState->markParsedVirginReplyAsWhole("ftpReadTransferDone code 226 or 250");
         ftpSendQuit(ftpState);
     } else {            /* != 226 */
         debugs(9, DBG_IMPORTANT, "Got code " << code << " after reading data");
@@ -2272,7 +2281,6 @@ ftpWriteTransferDone(Ftp::Gateway * ftpState)
     }
 
     ftpState->entry->timestampsSet();   /* XXX Is this needed? */
-    ftpState->markParsedVirginReplyAsWhole("ftpWriteTransferDone code 226 or 250");
     ftpSendReply(ftpState);
 }
 
@@ -2401,6 +2409,7 @@ ftpFail(Ftp::Gateway *ftpState)
     delete ftperr;
 
     ftpState->entry->replaceHttpReply(newrep);
+    ftpState->fwd->markStoredReplyAsWhole("ftpFail");
     ftpSendQuit(ftpState);
 }
 
@@ -2480,6 +2489,8 @@ ftpSendReply(Ftp::Gateway * ftpState)
 
     ftpState->entry->replaceHttpReply(err.BuildHttpReply());
 
+    ftpState->fwd->markStoredReplyAsWhole("ftpSendReply");
+
     ftpSendQuit(ftpState);
 }