itayd said
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I have IOT device that measures some sensors every 5 minutes and sending all the data just after 2 hours (24 messages).
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To send all accumulated data your device has to be online for 6 minutes (= 360 seconds = 24 msgs * 15 seconds).
I guess, the bulk update won't be implemented soon for ThingSpeak API...
Have you found a solution for your task with massive update?