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According to this forum, 302880 is the carrier code for a shared network being developed by Bell and TELLUS. Seems it will eventually show up as Bell for Bell Mobility subscribers, TELLUS for TELLUS subscribers, and it is uncertain whether it will continue to show up as 203880 on Rogers phones.

By the way, Google is your friend. Took me 30 seconds, maybe, to find this.
 
According to this forum, 203880 is the carrier code for a shared network being developed by Bell and TELLUS. Seems it will eventually show up as Bell for Bell Mobility subscribers, TELLUS for TELLUS subscribers, and it is uncertain whether it will continue to show up as 203880 on Rogers phones.

By the way, Google is your friend. Took me 30 seconds, maybe, to find this.

See that would make sense, but it says 302880, not 203880.
 
I'm in Calgary and I tend to get that same "carrier" code whenever I'm on the train and iPhone tries to reconnect to the Rogers network after emerging from a tunnel.
 
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