Eventually I get to the point where I need more throughput on my belt bus, so I use the upgrade planner and just sweep it across the whole thing..... Then I go have a nice home cooked meal as every construction bot in the base repeatedly:
- Flies to the chest
- Picks up a single belt
- Flies to the belt he's replacing
- Swaps them
- Flies to the storage chest
- Drops off one old belt
- Repeat, until it needs to recharge or the job is done.
Train rails are another excellent use for this. Using rail blueprints or even Ghost rail planner with bots doing batch rail placement would speed up the process significantly.