UMLsemantics questions

consider a class "C" with operation "o" and a method to implement this
operation. also suppose that "C" has a statechart that specifies the
reactive behaviour of its instances, but no transitions of this
statechart are triggered by "o".

if the statechart of an instance of "C" is blocked in the middle of a
run-to-completion step waiting for a synchronous call action to return,
and receives a request from another object to invoke "o", will it
execute the method of "o" or queue the request until the its
run-to-completion step is complete?

Thanks,
Pouria

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