diff --git a/rowers/dataprep.py b/rowers/dataprep.py
index bfd68570..acceef39 100644
--- a/rowers/dataprep.py
+++ b/rowers/dataprep.py
@@ -766,8 +766,12 @@ def fetchcp_new(rower, workouts):
     if len(data) > 1:
         df = pl.concat(data)
 
+
     try:
-        df = df.group_by(pl.col("delta")).agg(pl.max("cp"), pl.max("workout"), pl.max("url")).sort("delta")
+        #df = df.group_by(pl.col("delta")).agg(pl.max("cp"), pl.max("workout"), pl.max("url")).sort("delta")
+        df = df.groupby('delta').agg([
+            pl.all().sort_by('cp').last(),
+        ])
     except (KeyError, ColumnNotFoundError):  # pragma: no cover
         return pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64), 0, pl.Series(dtype=pl.Float64), pl.Series(dtype=pl.Float64)
 
@@ -1077,7 +1081,7 @@ def checkbreakthrough(w, r):
                         r.user.email,
                         r.user.first_name,
                         r.user.last_name,
-                        btvalues=btvalues.write_json())
+                        btvalues=btvalues.write_json(row_oriented=True))
         for coach in r.get_coaches():
             if coach.getemailnotifications and not coach.emailbounced:
                 _ = myqueue(queuehigh, handle_sendemail_breakthrough,
@@ -1085,7 +1089,7 @@ def checkbreakthrough(w, r):
                             coach.user.email,
                             r.user.first_name,
                             r.user.last_name,
-                            btvalues=btvalues.write_json(),
+                            btvalues=btvalues.write_json(row_oriented=True),
                             surname=True)
 
     # submit email task to send email about breakthrough workout
diff --git a/rowers/emails.py b/rowers/emails.py
index f0d4c0d9..424540dc 100644
--- a/rowers/emails.py
+++ b/rowers/emails.py
@@ -13,7 +13,7 @@ from scipy import optimize
 import rowingdata
 
 from rowingdata import rowingdata as rdata
-
+from rowers.utils import dologging
 from celery import app
 import datetime
 import pytz
@@ -132,7 +132,8 @@ def send_template_email(from_email, to_email, subject,
             except User.DoesNotExist:
                 pass
             except Exception as e:
-                pass
+                dologging('tasks.log',e)
+
 
     if not emailbounced:
         res = msg.send()
diff --git a/rowers/tasks.py b/rowers/tasks.py
index cf19d8dc..4dc9fc90 100644
--- a/rowers/tasks.py
+++ b/rowers/tasks.py
@@ -2160,10 +2160,13 @@ def handle_sendemail_breakthrough(workoutid, useremail,
                                   surname=False,
                                   **kwargs):
 
+    dologging('tasks.log',btvalues)
     btvalues = pd.read_json(btvalues)
+
     try:
         btvalues.sort_values('delta', axis=0, inplace=True)
     except KeyError:
+        dologging('tasks.log','KeyError')
         return 0
 
     lastname = ''
diff --git a/rowers/tests/testdata/testdata.tcx.gz b/rowers/tests/testdata/testdata.tcx.gz
index f4be04e3..cb98d752 100644
Binary files a/rowers/tests/testdata/testdata.tcx.gz and b/rowers/tests/testdata/testdata.tcx.gz differ
diff --git a/rowers/utils.py b/rowers/utils.py
index 9e7d5054..ee7ca475 100644
--- a/rowers/utils.py
+++ b/rowers/utils.py
@@ -361,9 +361,12 @@ def isbreakthrough(delta, cpvalues, p0, p1, p2, p3, ratio):
 
     pwr *= ratio
 
-    delta = delta.cast(pl.Int32)
-    cpvalues = cpvalues.cast(pl.Int32)
-    pwr = pwr.cast(pl.Int32)
+    try:
+        delta = delta.cast(pl.Int32)
+        cpvalues = cpvalues.cast(pl.Int32)
+        pwr = pwr.cast(pl.Int32)
+    except:
+        return False, pl.DataFrame(), False
 
     btdf = pl.DataFrame({
         'delta': delta,