My mods:

Tiny Owl:
I worked the lower mustard section for 9 rounds (1 more than pattern).
I worked the last round about 8 stitches beyond the end of the round.  This enabled me to finish at side on last round for ‘ears’ but to position the colour change jog so that I could hide it under one of the eyes over it.
I didn’t want to use safety eyes, so I worked the eyes as follows - using a 3.0mm hook, I worked 1 round of 6 sc in black, 1 round white 12 sc in white.
I crocheted the top together joining pairs of stitches under both loops with 3mm hook, working sc, dc in 1st pair of stitches, sc in next, ss across, sc in 2nd last, dc, sc in last.

Larger Owl:
I worked 2 extra increase rounds (i.e. 36 sc around) and 8 rounds of each colour on the sides to keep the proportions a bit.
I made the eyes larger by working the black round in sc as for tiny owl then the white round in dc instead of sc.

Thanks for a great pattern. I think it’s really clever that it’s so simple but super cute.