Been there, done this. :(
Including, taking too long to buy at the lowest priced / highest offered pack, and having everything go back from CDN$6.49 to CDN$12.99.
(Note to self ... when at this level, buy!)
Always buy every pack you can when you get to this lowest priced / highest offered level.
It takes 12 - 14 weeks for such offers to come back around again. [So no worries on your 6 week wait, you have 2 months more to go.]
From what I've seen $12.99 packs contain twice the materials (or sufficiently close enough) of $6.49 packs. But NOT twice the gold. It is arguable to forego the gold to be able to 'pack-up' twice as often. (? Guessing on twice as often - certainly it takes less than 12 -14 weeks to return to the same level of $12.99 packs.)
The 'normal' 'base' pack price you see matches the cost of the last pack you purchases. So -always- purchase the least expensive pack last.
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There seems to be 3 real pack sale points: Black Friday, Boxing Day, and May Day (?) [Easter?]. Buy. Moderated with the above. i.e. Buy all packs that may sense, least expensive last.
e.g. Last Black Friday Sale had a pack containing 1,000 Adrian and 1,000 Sixtus candles for CDN$25.99. In one pack you get close to max'ing out your Adrian and Sixtus. [Leveling them up is another story. Thus lots of errands needed.]
Correspondingly, packs had 1,000 candles for militant Inquisitors. Same idea.
