Did the atmospheric modeling change with 2.5.2?

[Nealius]

Did the weather modeling change between 2.5.0 and 2.5.2? I noticed my old METARs that I notated for my missions no longer have proper QNH. On 2.5.0, an ME QNH setting of 30.10 read 30.28 in the jet's altimeter on the ramp at Nellis. Now in 2.5.2 it reads 29.95.