Non-Reciprocal LOC & BC

This was from another group.

At KBOI, until the current release, the approach charts showed, for the
ILS10R and LOC BC 28L approaches magnetic courses of 100° and 278°
respectively.

The JEPP charts were changed with the current release; but the NACO charts
probably still show it:

http://naco.faa.gov/d-tpp/0610/00057IL10R.PDF
http://naco.faa.gov/d-tpp/0610/00057LBC28L.PDF


Could this have to do with the changes in magnetic variation when the
charts were issued?

In other words, if the charting method for a LOC course merely takes the
true course, and then applies magnetic variation; and if the source showed
different values for these two approaches, could that result in this
apparent discrepancy?

www.airnav.com does show (at least as of this morning) a two degree
difference between the mag var for the airport, and that for the ILS10R
approach.
Ron (EPM) (N5843Q, Mooney M20E) (CP, ASEL, ASES, IA)