As you work on the new one and as you do an upgrade on the existing one you may wish to have a look at the spec data. Some information might be described a little clearer.
E.g., 0.001% accuracy: this is ususally split into offset and gain and also there is an aging attached to it (not yet established, understand, but...). You will probably not specify 0.001% absolute accuracy (10ppm) of output at any voltage and after say e.g. 10 months. my guess is your voltage standard inaccuracy is maybe already half of it, so not that much left over by the device itself.
Temperature range... I would think, actually, CE had demanded a temp range definition anyhow, so maybe just a miss in transferring this into the manual.
Will help you avoid to not meet expectations you never wanted to meet anyway. And facilitates its use.