Yes you can switch from one to the next on one day. The dose should be the same - your insulin to carb ratios are unlikely to change.
It starts acting quicker but lasts as long as NovoSloggish.
How far in advance depends on the person and the food you eat. When I migrated, I started off injecting just before I ate and kept an eye out for spikes on my Libre chart. If I saw a significant spike, I moved the dose earlier. I now find I inject about 30 minutes before breakfast but only 10 minutes before most other meals. Like everything else it takes some trial and error
It is quicker at any corrections and can be used for DP correction .,.. and miscalculated carb corrections and stress corrections and ...