[BioC] how does an annotation package handle ambigious probe set id mappings

[Andrew Yee]

Apologies if this has been asked before, but how does an annotation
package handle an ambiguous probe set ID mapping?

Take for example the Affymetrix chip U133X3P.

When I use the annotation for this chip for probe set ID
1552641_3p_s_at, it returns only one match:

> library('u133x3p.db')
> mget('1552641_3p_s_at', env=u133x3pSYMBOL)
$`1552641_3p_s_at`
[1] "ATAD3B"
> mget('1552641_3p_s_at', env=u133x3pENTREZID)
$`1552641_3p_s_at`
[1] "83858"

However, when I search Affymetrix, with:

https://www.affymetrix.com/analysis/netaffx/fullrecord.affx?pk=U133_X3P:1552641_3P_S_AT

it states that it ambiguously maps to three gene symbols, ATAD3A,
ATAD3B, and LOC732419.

How does the annotation package determine which gene symbol it should map to?

Thanks,
Andrew