I have been trying to reach someone via email. Is it possible to do late checkout on our last night?
I have no idea but I did find them extremely obliging and would be surprised if if they did not comply.
I had to contact them myself before we stayed, I found them good to answer quickly from the booking/com messaging link on our reservation. I am not sure about their direct e-mail. I know they are nearly full all year round as I asked them for an early check-in but it was impossible because they were so busy. You could try calling them directly? Sorry I could not help you more.
Get an answer from Olaias Park Hotel staff and past guests.