I'm trying to send multiple notifications using my PHP script. But after sending about 50 or so out of the 10k users, I get a broken pipe warning. I'm not sure whether that message is sent. From various other posts, I learnt that it could be because of a invalid token. However, my feedback service returns no invalid tokens. (ssl://feedback.push.apple.com:2196) Tried this both in production mode and sandbox mode.
What other reasons could cause this invalid pipe issue?
My exact problem is explained here by someone else as well.