I went back fulltime when my ds was pretty exactly 18 month old. He adjusted just fine. I worked parttime since he was 12 month, and he started daycare than.
We have a daycare center with after hour care, and all the kids are in one group than with different carers, so he had to adjust to the new people, but it really took only a couple of days. He has his big sis with him, though. (but not in the normal daycare group)
I think it was so the right decision. I used to work parttime when dd was small, and I hated it. I kind of missed all the important stuff, was not treated like a full member of the team and was constantly stressed. It is much better now.
I get the full benefits, I am able to build my retirement plan and I feel like a complete person. My kids are totally used to it and I guess they are quite happy.
I think every child and every family is different. You´ll have to find your own way. But how do you feel about the decision? Do you feel excited if you think about the interview and the job? Would you be sad if you would not get it? visualize and feel how you feel in these situations.
Hope that helps!