I agree with calmbeforestorm that Sprott seems to have major...

I agree with calmbeforestorm that Sprott seems to have major interpretation based on information supporting the revised reserves lacking certain details. I have compared values of certain parameters with those provided in the PFS and I cannot see a major negative shift.

Metal Prices

Metal PDF Latest Reserves Change (%)

Ag (US$/oz) 25.5 23.0 -9.8
Zn (US$/lb) 1.26 1.11 -11.8
Au (US$/oz) 1,873 1,912 2.1
Pb (US$/lb) 0.88 1.03 17.5
Cu (US$/lb) 3.53 3.78 7.1

Given the dominant impact of Ag and Zn on revenue, the above indicates the roughly 10% drop in value as per Sprott, possibly a bit better.

However, the metallurgical performance numbers, where provided are better than per PDF, as shown below.

Metal PDF Latest Reserves Change (%)

Into Pb-Ag concentrate:
Cu 80 81.2 1.5
Pb 85 87.4 2.8
Zn 11 N/A
Ag 69 75.0 8.7
Au 38 N/A

Quality of Pb-Ag concentrate
Pb 41.4 47.4 14.5
Ag 1,892 2,266 19.8

Into Zn- concentrate:
Cu 24 N/A
Pb 19 /A
Zn 80 80.2 0.3
Ag 19 N/A

Au 24
Quality of Zn concentrate
Zn 57.1 57.9 1.4

In other words, better recoveries should to some extent compensate for lower prices. The fact that no information is given on certain metals in particular concentrates is in my opinion a reflection that these contributed little and are therefore not that material, not that their contribution has dropped to nil. This is confirmed by the two last complete sentences on page 9:
The Ag/Pb concentrate contains payable Ag, Pb, Zn, Cu, Sb and Au (Sb is payable if over 2% and if Ag is over 2,500g/t and Zn is payable if over 10%). The Zn concentrate contains payable Zn, Ag, and Au.

May I suggest that a report by an agency known to take positions should not be taken too seriously. The may have all sorts of agendas.