Which build do I have

Every FlightStream install prints its release name and its build number when it starts. That PAIR is what identifies a build. Neither half does it alone: 7 registered builds print the same release name as at least one other, and the name the vendor sells a build under is not always the name the binary prints.

Read the two values off that line, find the row carrying both, and pass the identifier beside them wherever this package asks for a version. The columns are the two values rather than the whole line, because the line is not byte-identical across builds: the 25.0 solver writes a NUL byte into it where the newer builds write a space, which a terminal draws as a space and a comparison does not (RPT-023).

Release name it prints	Build number it prints	Pass this	Vendor ships it as
25.0	#12162024	25.000	25.0
25.1	#5062025	25.100	25.1
26.0	#10202025	26.000	26.0
26.1 (shared)	#2122026	26.100	26.1
26.1 (shared)	#5012026	26.101	26.1
26.1 (shared)	#7012026	26.120	26.12 (not what it prints)
26.1 (shared)	#7262026	26.121	26.12 (not what it prints)
26.1 (shared)	#8092026	26.122	26.12 (not what it prints)
26.1 (shared)	#8112026	26.123	26.12 (not what it prints)
26.1 (shared)	#8172026	26.124	26.12 (not what it prints)

Reading the table

The identifiers in the Pass this column are this package's own, in the YY.XXX scheme: the vendor major, the minor release, and a last digit that indexes builds within that release. That last digit is an ORDERING position and not a claim of descent, so a build at a hotfix index is not necessarily a hotfix of the one before it.

A printed name marked (shared) is printed by more than one registered build: 26.1. Match on the build number, which is unique. Passing a shared release name to this package is refused rather than resolved to one of the builds, and the refusal lists the candidates by build number.

The last column is the name the vendor sells the build under, which is the name that appears in release notes and download pages. Where it says not what it prints, the binary states a different release name about itself, so a reader matching on the sold name would land on the wrong row. Match on what your install prints.

A build number recorded here comes from the solver's own banner captured in a committed report, never from a note or a recollection. That is why a newly registered build can appear with no number: it is registered before it is run.

Registered is not the same as supported. What each build can actually do is on the compatibility matrix, and the level each one has reached is in pyflightstream.support_table().