I would like to prepare for a long route (700 m altitude gain, 12-16 hours, including descent, with alpine start), one like which I have never [successfully] climbed before. It involves many sections of roped climbing, mixed with longer sections of what should be unroped exposed scrambling. I have done longer easy routes (ones not requiring a rope), and shorter trad routes (roped climbing all the way up).
The problem for me there is the change from roped to unroped climbing and back. When I decide where I need to change, it's usually too late, and every such mistake costs time. For example, if we climb without a rope and get to a more technical place, it's usually very inconvenient (=wasting time) to unpack the rope. And the other way around: if we climb with rope and protection, and come to a section that doesn't require it, I have to realize that early (which I usually fail), so we can pack the rope and move more quickly.
So it's the mixture of "roped" and "unroped" that makes me waste a lot of time and abort the route (2 unsuccessful attempts so far on similar routes). I would like to do some training in that regard; however, here is my problem:
I don't have proper mountains where I live; ones that come close are 200-300 metres high and easier than needed; we also have 1-pitch routes of any difficulty but I guess this doesn't help at all.
So how can I prepare as good as I can for such a route? Should I climb the short sections I have access to, repeatedly (it gets boring, really fast)? In bad weather? With an oversized backpack?
P.S. I have inflated the expected time for the route; it's 8-12 hours officially but experience shows that I have to apply some factor to it.