I have been working on a system alone for about two years. I inherited the system from a contractor who spent about two years working on it before me (alone).  The system is not particularly well designed because there is business logic, presentation logic and data logic mingled together.  It is a very complex system, which I am trying to refactor as I go along and this takes time.A new developer was recruited but he seems to be taking more of a Project management role.  He is very direct asking exactly how long things will take; questioning all my assumptions and predictions, which is difficult because of the complexity and because I am the only expert at the moment.I am very organised in my personal life.  For example, I was asked what time I would arrive in Manchester last week so I provided an exact time catering for accidents and road works on the way.  I find it difficult to apply the same principles at work in software development at the moment.Don't get me wrong.  I have worked with project managers on less complex projects in the past and have had a good relationship, but then the projects were less complex and I always delivered before schedule.  I am struggling with this particular project manager and it is causing stress.How do other developers deal with project managers who want answers and accurate deadline dates?
Setting Deadlines in software development
design patterns;teamwork;estimation;time estimation