After a conversation with Lance Shaner, Owner of Omega yeast, the following was added to the FAQ section of their website:
My pack of yeast is swollen. Is the yeast still good to use?
Swelling of the pack is not an indication of a problem with the yeast. It is the result of slow fermentation of residual fermentables during storage. The yeast is still perfectly fine to use (assuming it is within date and has been stored properly).
A Lactobacillus brevis and plantarum blend with a wide temperature range. The L. plantarum, isolated in collaboration with Marz Community Brewing, sours efficiently at its higher end. Do not sour above 95°F (35°C) to prevent stalling. Max souring develops within 24 to 72 hrs. Extremely hop sensitive, however, even 2 IBUs can prevent souring.
Bretts, Blends + Bacteria
68–95° F (20–35° C)
We strongly recommend purchasing an ice pack with your liquid yeast to help maintain a reduced temperature during shipment.