The Wyeast liquid yeast can survive warmer temperatures for some time and still be viable. Although the longer they are kept above 40F the less viable they will become. The only way to know for sure is to activate the pack and see if it expands due to activity. I would advise you do this before you start brewing to confirm that you have active yeast to pitch when you are finished. If the yeast is not active I would postpone brewing until replacement yeast is available.
There are a few yeast strains that Wyeast produces that have a tendency to inflate partially prior to activation and 1056 American Ale is the prime suspect. The slight inflation is due to residual CO2 in solution left over from propagation being released. Wyeast has a process to remove most of the CO2 prior to packaging but for some reason 1056 wants to hold on to some. The CO2 is released when the temp is raised and the package is agitated, this happens quite often when shipping the yeast.
The swelling can also be attributed to minimal amounts of propagation media making it into the package. In this case the swelling is actually a sign of healthy yeast that is more active due the increase in temperature.
In either case it is best to refrigerate as soon as possible. You should also try and use any yeast exposed to extreme temperatures as soon as possible or to make a yeast starter to build up the yeast cell count. A starter can be made immediately and then stored in the refrigerator for a few weeks before pitching.