If you opt for sandals, please apply the oversize boot fitting suggestions if you plan to wear socks, which is recommended. But, each peregrino has their own walking style and preference.
I have Keen Arroyo II hiking sandals. I use them here in Florida, as it is rather warm for enclosed boots. But, I still wear two pair of socks when hiking.
Also, a closed toe box is a MUST to protect your toes on downhill and rocky segments.
Finally, do carry extra socks. You WILL encounter prodigious mud through the end of June. Your feet will get caked with mud each day. Either "go commando" and just rinse the sandals and feet as needed, or change socks - a lot.
I hope this helps.