I finished it on time!!!
I used the free Spring into Summer Blanket pattern, with the exception that I switched yarns every row. I had about a million yarn ends to weave in, but I was able to use up most of the Red Heart Gumdrop and Loops and Threads value pack yarn that I had on hand.
I worked 54 rows before I started to decrease. The finished blanket is about 4' x 4' - I hope the wee recipient can get a few years of enjoyment out of it before she outgrows it!
I think this pattern is really better suited for self-striping or solid yarns - but I am still happy with the end result. It took a total of about 1760 yards of worsted weight yarn using a G hook.