What's your problem? Show-time is show-time. If your employer briefs you to show up at ETD-45, then you do that and if you depart with delay then that is the problem of the operator, not yours.
On the other hand it is not a big problem to prepare an aircraft in a few minutes. For a ferry flight you can easily show up 45 minutes before ETD, if you are in the right location, if you have fuel loaded and if all crew members are fully aware of what they need to do to make it happen. No, there won't be much time for a cup of coffee and this kind of nonsense: collect your paperwork, go to the plane, prepare the thing, start up and go.