[OCMock]A question about the andDo function

Question

1.code show as below：

[[OCMExpect([[self.mockDelegate ignoringNonObjectArgs] adLoaded:OCMOCK_ANY statusChanged:statusStarted]) ignoringNonObjectArgs] andDo:^(NSInvocation *invocation) {
        ...
        ...
    }];

I broke the point and found that andDo is only executed works once(when status==statusStarted).The function is not triggered when status==statusEnded. But when I copied the above code and found that the andDo function was triggered when status==statusEnded. code show as below：

[[OCMExpect([[self.mockDelegate ignoringNonObjectArgs] adLoaded:OCMOCK_ANY statusChanged:statusStarted]) ignoringNonObjectArgs] andDo:^(NSInvocation *invocation) {
        ...
        ...
    }];
[[OCMExpect([[self.mockDelegate ignoringNonObjectArgs] adLoaded:OCMOCK_ANY statusChanged:statusStarted]) ignoringNonObjectArgs] andDo:^(NSInvocation *invocation) {
        ...
        ...
    }];

what's the reason？

2.an additional question

After experimenting I found that OCMVerifyAllWithDelay(self.adMockDelegate, 10) is not equivalent to：

 dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(10 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{    
 OCMVerifyAll(self.adMockDelegate);
    });

OCMVerifyAllWithDelay blocks the thread for 10 seconds,instead of extending the verification time of the mock by 10 seconds.why？