Please elaborate: I do not understand what you mean.
I see your edit now ! Explanation.
A user of fpcupdeluxe chooses a FPC version to install.
This version gets downloaded.
Fpcupdeluxe scans the makefile of the sources to decide which bootstrapper to use.
It uses the lowest version that is allowed by the makefile itself.
E.g. trunk makefile allows for 3.0.0 and 3.0.2
REQUIREDVERSION=3.0.0
REQUIREDVERSION2=3.0.2
It chooses the lowest due to the limited availability of official bootstrappers.
And fpcupdeluxe will build a bootstrapper itself if even the lowest is not available.
To bootstrap this bootstrapper, the same procedure as above is used.
And if that is not working:
https://github.com/newpascal/fpcupdeluxe/releases/tag/bootstrappers_v1.0