diff --git a/calendars/graphblas.yaml b/calendars/graphblas.yaml
index fa958f3..ec640d0 100644
--- a/calendars/graphblas.yaml
+++ b/calendars/graphblas.yaml
@@ -1,5 +1,4 @@
 name: GraphBLAS Community Calendar
-timezone: America/Los_Angeles
 events:
   - summary: Python-graphblas Community Call
     description: |
@@ -14,8 +13,8 @@ events:
       Zoom meeting ID: 972 6723 4756
       Zoom meeting passcode: 584468
 
-    begin: 2023-08-16 07:00:00
-    end: 2023-08-16 08:00:00
+    begin: 2023-08-16 14:00:00
+    end: 2023-08-16 15:00:00
     url: https://anaconda.zoom.us/j/97267234756?pwd=Q00wSjE2dDV6NmF3eFBZSFBtVDFSQT09
     repeat:
       interval:
@@ -31,7 +30,7 @@ events:
       Zoom meeting ID: 160 627 7061
       Zoom meeting passcode: 677995
 
-    begin: 2023-09-08 09:00:00
-    end: 2023-09-08 10:00:00
+    begin: 2023-09-08 16:00:00
+    end: 2023-09-08 17:00:00
     url: https://mitll.zoomgov.com/j/1606277061?pwd=YUdEZGlkV1lCbUlITEhaak9MdTJvUT09
     ics: RRULE:FREQ=MONTHLY;BYDAY=2FR
diff --git a/calendars/networkx.yaml b/calendars/networkx.yaml
index 4f28a0c..06fcb37 100644
--- a/calendars/networkx.yaml
+++ b/calendars/networkx.yaml
@@ -1,5 +1,4 @@
 name: NetworkX Community Calendar
-timezone: America/New_York
 events:
   - summary: NetworkX Community Call
     description: |
@@ -7,7 +6,7 @@ events:
 
       Meeting link: https://colgate.zoom.us/j/92619161786
       Meeting notes: https://hackmd.io/ea2IhUuqSrG4kM9tokXuEw
-    begin: 2025-05-29 12:00:00
+    begin: 2025-05-29 16:00:00
     duration: { minutes: 60 }
     url: https://colgate.zoom.us/j/92619161786
     repeat:
@@ -23,7 +22,7 @@ events:
       Meeting notes: https://hackmd.io/rqs_pWMxSLmICXCpI3w-Ug
       Zoom meeting ID: 941 9287 4965
       Zoom meeting passcode: 572126
-    begin: 2025-02-25 11:30:00
+    begin: 2025-02-25 15:30:00
     duration: { minutes: 60 }
     url: https://anaconda.zoom.us/j/94192874965?pwd=K0wvcmhXem41ZlVSQ2l4TXlUaDgxdz09
     ics: RRULE:FREQ=MONTHLY;BYDAY=1TU;INTERVAL=1
@@ -34,7 +33,7 @@ events:
 
       Meeting link: https://colgate.zoom.us/j/281534728
       Meeting notes: https://hackmd.io/tF0saJhyQ2i25e8tWiBrmw
-    begin: 2025-05-15 13:00:00Z
+    begin: 2025-05-15 13:00:00
     duration: { minutes: 60 }
     url: https://colgate.zoom.us/j/281534728
     repeat:
diff --git a/calendars/podcast.yaml b/calendars/podcast.yaml
index 7a5fddc..fb0ddc1 100644
--- a/calendars/podcast.yaml
+++ b/calendars/podcast.yaml
@@ -1,10 +1,9 @@
 name: Podcast Calendar
-timezone: America/Los_Angeles
 events:
   - summary: Another Open Source Podcast
     description: |
       A podcast about open source! Join us for discussions on open source
       events, documentation, developer testimonies, mentorship programs and more."
-    begin: 2024-05-10 11:00:00
-    end: 2024-05-10 12:00:00
+    begin: 2024-05-10 18:00:00
+    end: 2024-05-10 19:00:00
     url: https://discord.gg/X3fpKzKf
diff --git a/calendars/sparse-array.yaml b/calendars/sparse-array.yaml
index 0a77374..be12b01 100644
--- a/calendars/sparse-array.yaml
+++ b/calendars/sparse-array.yaml
@@ -1,18 +1,17 @@
 name: Sparse Arrays WG
-timezone: America/Los_Angeles
 events:
   - summary: Sparse Array Work Session
     description: |
       Meeting Link:  https://meet.google.com/jrp-qgcf-nxh
       Meeting notes: https://hackmd.io/9UCjKdRUTEeoS8KdQNll-A
-    begin: 2024-01-08 11:00:00
-    duration: { minutes: 60 }
+    begin: 2024-01-08 18:00:00
+    end: 2024-01-08 19:00:00
     url: https://meet.google.com/jrp-qgcf-nxh
     repeat:
       interval:
         days: 14
       until: 2025-12-31 00:00:00
       except_on:
-        - 2024-09-02 11:00:00
+        - 2024-09-02 18:00:00
       also_on:
-        - 2024-08-26 11:00:00
+        - 2024-08-26 18:00:00
diff --git a/calendars/specs.yaml b/calendars/specs.yaml
index ab9725b..cc4202b 100644
--- a/calendars/specs.yaml
+++ b/calendars/specs.yaml
@@ -1,5 +1,4 @@
 name: SPEC Steering Committee
-timezone: America/Los_Angeles
 events:
   - summary: SPEC Planning Meeting
     description: |
@@ -7,7 +6,7 @@ events:
 
       Meeting Link:  https://ucsc.zoom.us/j/98441337155?pwd=Mjl6TjdRTTNBc3ZGQzE3MTQyRVkyZz09
       Meeting notes: https://hackmd.io/WPTkRnNtSOeF7OhUTRHDwA
-    begin: 2023-09-05 9:00:00
-    end: 2023-09-05 10:00:00
+    begin: 2023-09-05 16:00:00
+    end: 2023-09-05 17:00:00
     url: https://ucsc.zoom.us/j/98441337155?pwd=Mjl6TjdRTTNBc3ZGQzE3MTQyRVkyZz09
     ics: RRULE:FREQ=MONTHLY;BYDAY=1TU;INTERVAL=1