diff --git a/fifo/timezones.py b/fifo/timezones.py
index 4943a17..5e46af5 100644
--- a/fifo/timezones.py
+++ b/fifo/timezones.py
@@ -41,7 +41,7 @@ def assemble_timezones():
     timezones["AZOT"] = timezone("Atlantic/Azores")  # Azores Standard Time (UTC−01)
     timezones["AZT"] = timezone("Asia/Baku")  # Azerbaijan Time (UTC+04)
     timezones["BDT"] = timezone("Asia/Brunei")  # Brunei Time (UTC+08)
-    timezones["BIOT"] = timezone("Etc/GMT+6")  # British Indian Ocean Time (UTC+06)
+    timezones["BIOT"] = timezone("Etc/GMT-6")  # British Indian Ocean Time (UTC+06)
     timezones["BIT"] = timezone("Etc/GMT+12")  # Baker Island Time (UTC−12)
     timezones["BOT"] = timezone("America/La_Paz")  # Bolivia Time (UTC−04)
     timezones["BRST"] = timezone("America/Sao_Paulo")  # Brasilia Summer Time (UTC−02)
@@ -63,7 +63,7 @@ def assemble_timezones():
     timezones["CHOT"] = timezone("Asia/Choibalsan")  # Choibalsan Standard Time (UTC+08)
     timezones["CHST"] = timezone("Pacific/Guam")  # Chamorro Standard Time (UTC+10)
     timezones["CHUT"] = timezone("Pacific/Chuuk")  # Chuuk Time (UTC+10)
-    timezones["CIST"] = timezone("Etc/GMT-8")  # Clipperton Island Standard Time (UTC−08)
+    timezones["CIST"] = timezone("Etc/GMT+8")  # Clipperton Island Standard Time (UTC−08)
     timezones["CIT"] = timezone("Asia/Makassar")  # Central Indonesia Time (UTC+08)
     timezones["CKT"] = timezone("Pacific/Rarotonga")  # Cook Island Time (UTC−10)
     timezones["CLST"] = timezone("America/Santiago")  # Chile Summer Time (UTC−03)
@@ -119,7 +119,7 @@ def assemble_timezones():
     timezones["HOVT"] = timezone("Asia/Hovd")  # Khovd Standard Time (UTC+07)
     timezones["ICT"] = timezone("Asia/Ho_Chi_Minh")  # Indochina Time (UTC+07)
     timezones["IDT"] = timezone("Asia/Jerusalem")  # Israel Daylight Time (UTC+03)
-    timezones["IOT"] = timezone("Etc/GMT+3")  # Indian Ocean Time (UTC+03)
+    timezones["IOT"] = timezone("Etc/GMT-3")  # Indian Ocean Time (UTC+03)
     timezones["IRDT"] = timezone("Asia/Tehran")  # Iran Daylight Time (UTC+04:30)
     timezones["IRKT"] = timezone("Asia/Irkutsk")  # Irkutsk Time (UTC+08)
     timezones["IRST"] = timezone("Asia/Tehran")  # Iran Standard Time (UTC+03:30)