Before Blocking
Side to side: 37in
Top to bottom: 17in.

After Blocking
Side to side: 43in
Top to bottom: 23in

I did as the pattern suggested and slipped the first stitch of every row. While it may create a smoother finished edge, (I didn’t notice) I think it made for a tighter edge and thus I wasn’t able to stretch it as much. When I do this pattern again I will simply knit the first stitch rather than slip it.