Ahh, that makes more sense. I didn't even think about it that way because the struct I have from April 2 2012 shows the following structure:
Code:
[OPCode: 0x6537] OP_MercenaryDataUpdate [Server->Client] [Size: 93]
00 00 00 00 - 0 - MercStatus
01 00 00 00 - 1 - MercCount
8f 01 00 00 - 399 - MercID
e4 66 ab 13 - 330000100 - MercType
09 b5 ab 13 - 330020105 - MercSubType
bb 00 00 00 - 187 - PurchaseCost
b2 00 00 00 - 178 - UpkeepCost
01 00 00 00 - 1 - Status
00 00 00 00 - 0 - AltCurrencyCost
01 00 00 00 - 1 - AltCurrencyUpkeep
13 00 00 00 - 19 - AltCurrencyType
00 - 0 - MercUnk01
a0 bb 0d 00 - 900000 - TimeLeft
05 00 00 00 - 5 - MerchantSlot
01 00 00 00 - 1 - MercUnk02
02 00 00 00 - 2 - StanceCount
88 d5 8b c3 - 3280721288 - MercUnk03
01 - 1 - MercUnk04
4b 65 6b 6c 65 6b 00 Keklek - MercName
00 00 00 00 - 0 - StanceIndex
01 00 00 00 - 1 - Stance
01 00 00 00 - 1 - StanceIndex
02 00 00 00 - 2 - Stance
01 00 00 00 - 1 - MercUnk05
Note the additional fields I saw are in green, and MercUnk03 also has some data in it in the VoA collect, where yours looks almost just like what they do when sent as a merchant list with no data in MercUnk03.
Maybe they used to use the same structs for merchant lists and the data updates, but changed that later in VoA since some things like the MercTypes list are unneeded.
Either way, at least both versions are in this thread as examples for that packet, which may help for comparison purposes.