It has been months since I communicated directly with Jennifer so I can't comment on whether she is surly or petty these days. I seriously doubt she is lazy though, based on the number of shops she seems to schedule.
In my experience, she is much less responsive to shoppers than, let's say, 10 years ago. When she responds, her responses are often brief. I guess her brief responses can come across as curt or even surly.
But then again, she is also much busier than she was 10 years ago. That's not an excuse. It's just an observation. It also doesn't help that the huge MSC she mainly schedules for is not known for being responsive to shoppers.
Schedulers and editors are usually powerless to waive most shop requirements. It is not fair or even useful to blame/attack schedulers and editors for not accepting shops when shoppers didn't/couldn't meet all the requirements. OTOH, it is only professional to respond, if only to let the shoppers know whom they should contact.