Yes, there are several reasons not to want to only start on one's images at home.
I am pretty organized with my workflow so the time taken to import, add metadata, keyword etc will not take long.
I use a lot of presets too.
In the case of this trip I will be well prepared since I know where I am going and, roughly, at least my likely subjects.
I have an extensive keyword hierarchy (25 000 keywords) that will grow during this trip with mostly location keywords for small places in South Africa, Botswana, and Namibia although I will try as much as possible to be prepared prior to departure, but from experience this will never be complete.
The middle of the day will be my most likely time work on images.
Early morning and late afternoon I will very preferably be shooting.
I am expecting to get pretty tired so even after 20:00 I expect to be asleep for an early start the next day at 04:00.