This summer I'm planning to mount my first 4000 m mountain in Switzerland. So far I only got around 3300 meters while hiking and had no problems. However 4000 meter an above is definitively a different category.
Since my goal requires a little bit of experience how to cross a glacier, I will do this in a guided tour, since it is my first time. There are basically two opportunities:
1) On day 1 arrive around lunch time on a mountain hut located around 3600 m. Do some hikes in the near surrounding and stay there over night to acclimatisation a little bit. On day 2 in the early morning go up to the mountain (4050m) and descend to 500m and go home.
2) Arrive early on the first day, go up to the mountain and in only a few hours back to 500m. This would include a visit of approximately 5 hours on altitudes higher than 3000m.
Now if heard, that if you're staying only a very short amount of time on high altitudes (a few hours) you probably won't get any altitude problems. That would justify to choose option 2. On the other hand, acclimatisation isn't a bad thing, but is less than 24 hours as planned in option 1 reasonable?