Simple knit pattern change question

I’m getting ready to start a very simple afghan pattern that calls for the whole 4.5’X 6’ to be done in moss stitch. While learning the moss stitch I discovered that I like the look of not alternating the rows. I like it better with all the rows being just a knit/purl pattern on every row. Will that change the amount of yarn I need or size of the afghan?:knitting:

The best way to know is to make a sample. Do it in the original pattern, maybe about 5 or 6" square. Measure it, see how many rows and sts that is, then putting a slipknot where you finished, measure out the yarn it took. Do it in the other pattern, same number of sts and same number of rows. Then measure that one and note if it’s the same size square and if you go past the slipknot or finish before it.