Many were produced however most were recalled when they announced the upgraded security notes.
As you may recall - the upgrade occurred in 2004 (with the arrival of BEU- BEW upgraded security thread notes). It is believed that most of the 2004 BES & 2004 BER notes made it into circulation simply because they were most accessible when stored & then released into circulation. It is believed that the 2003 BER/BEL might have been stored deepest in the BOC or distributer/bank vaults and were accessed last (or when they were accessed/left over- they were recalled in large batches and thus destroyed). Only small numbers of this prefix were discovered in small ranges.
A similar theory applies to the 2003 BEK (change-over). Most BEK notes were found as inserts in other prefixes so that just the regular issue of BEK (BC-63c) commands more than the insert (BC-63cA). Most of the BEK's were caught as inserts first and then a few non-inserts were discovered later (notes which fell outside the determined SN range). It is likely only a few "trickled out" into circulation.
A significant and wide range of BEP notes were reported - so it was likely that a good portion of that prefix was released (yet far fewer then the full 10,000,000 run). Unlike the BEL, 2003 BER, which caught us collectors off-guard, by this time most of us were becoming aware of the discrepancies (the likelihood of the recall) so many of us were keeping our BEP's (& desperately searching for the other three- 2003 BEK, BEL & BER). Hence, BV is not just about how many found their way to circulation but also about how many were found/kept by collectors (& in what shape).
If you check the SNDB you will observe that the notes entered rarely follow a logical pre-determined pattern. This may be due to who finds the notes, who enters them (into the SNDB) and also on the way the notes are typically released in a somewhat random order across various regions of Canada.