There's already a pre-existing thread where that question was answered. The demand is far too low and the cost for the phones is much higher. Samsung Canada still won't post specs on their website confirming the 64GB one even exists, which likely means they're still having supply issues.
In terms of announcing new devices, short of the initial announcement when a new device (base model usually) becomes available, there won't be others when higher storage models are out. Rogers didn't make a single announcement when they got some 64GBs in stock, and still haven't.
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