Sounds like your job is similar to mine, in that I'm largely working from a desk but have to walk along a 30 yard corridor fairly often each hour.
I went back just before the 6 week point, last week. It honestly hasn't been too bad. As long as I use a stick to walk it's fine. Start up pain is a bit uncomfortable, though. Although I haven't really managed my exercises since being back, in a way, I think it helped as I was effecitively doing exercise of a different sort. By the Friday I was quite sore and started my (overdue) op physio, which I think has helped.
The main problem, for me, at least, was that once I was back I was expected to work at normal capacity, but I have been very firm about what I will and won't do. If at all possible, I strongly suggest you do that, too.
Ideally, perhaps I might have had another two weeks off, but, to be honest, I was desperate to return as I love my job. (I suspect my long suffering family were quite relieved, too!).
I see quite a few people get back in much shorter time but some take a fair bit longer, so, as always, it's an individual thing. I'm afraid you won't really know until you see how you are after the op.
The main thing to remember is that you've got many years ahead in which to impress your boss, so don't rush back!
Best wishes and good luck.
Andy