Vehicles can't deliver material for construction if behind a pipe/belt?

Issue description

I couldn't see this mentioned elsewhere, or couldn't see a decent answer.
I've noticed that If I first design a layout using Planner mode, then selectively build certain parts, other parts that I build afterward that aren't directly reachable, because they're surrounded by buildings/pipes/belts etc., that they will never have parts delivered, and I must use unity.
Is this a current limitation, where vehicles can't deliver items to constructions in this scenario?
I thought they could always do this, and/or they have a maximum range, where all they need to do is sit inside this range to deliver.
Save file attached. Currently there is a Data Center and 2 Water Chillers in this situation. It is waiting on Electronics III. There is a storage which is full of them, with vehicle export set to On. Neither are paused. I have paused and unpaused them. There are vehicles available.
Actually just now I saw an alert that a truck is unable to reach a location, and selected it to discover that it is indeed targeting those buildings.
Save 2024-07-09, 20-54-34.save

Reproduction steps

1. Load attached save
2. Find mentioned Data Center right beside an array of Rainwater Harvesters
3. Wait

Game version and build number

v0.6.4d b343

Operating system

Windows

The range is limited to one tile from building. Just don't put the pipes before the building is built.

Ok thanks. Maybe this can go under the 'feature request / vehicle improvement' umbrella.