Production was running great, volume, cost -wise, but sales were underwhelming. Up only 10% from Q4. We need to consider they built inventories, shipped quite less than produced.
They provide an explanation that hints at strong Q2 (bold is mine):
"Reflecting the lag between orders and shipments, the significant majority of these price gains will be realized in the second quarter."
It seems the "missing" earnings are in inventories. It's not hidden, it's disclosed, but keep in mind these bulked-up pulp inventories are carried at cost... In sum, it’s postponed. Bummer for short term traders. Headlines of sales/earnings are not enough to gauge Q1, must look at the improving book value, inventories, and consider realization lag. More price increases from April, steady futures, and this same lag effect should carry beyond Q2 into a strong Q3. Still bullish and patient for the reward.