ENSPOST precipitation fields

[Mandelli Alessandro]

I downloaded enspost.t12z.prcp from
ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/mrf/prod

Then I tried wgrib -verf -v enspost.t12z.prcp

This is an excerpt:

624:7488337:D=2005012812:APCP:sfc:kpds=61,1,0:0-6hr acc:ens+5:"Total
precipitation [kg/m^2]
625:7500264:D=2005012812:APCP:sfc:kpds=61,1,0:0-12hr acc:ens+5:"Total
precipitation [kg/m^2]
626:7513505:D=2005012812:APCP:sfc:kpds=61,1,0:12-18hr acc:ens+5:"Total
precipitation [kg/m^2]
627:7526746:D=2005012812:APCP:sfc:kpds=61,1,0:12-24hr acc:ens+5:"Total
precipitation [kg/m^2]

This is apparently wrong to me, since the base timestep is 6 hours, also
the apcp must be on a 6-hours accumulation time.
If I grep out by member (ens+5), I got twice the timesteps and one in
two has 12-hours acc pcp. Unfortunately, I've got no regular expression
for grepping out the extra records.

Any thought anyone?