In the UK, "shedyule" would be more likely.
In Canada, it seems very much to depend on background and education. I hear both, regularly.
There is something of a joke, which more or less states that the pronunciation of "schedule" depends on whether one went to "skool" or "shool." This is intended to represent the difference between the sounds of the initial letter combination.
It's a bit silly, but it does make a point that more than one pronunciation is acceptable.
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