creating a formula to calculate number of meals based on date and time for billing

I am trying to write a formula that will calculate the number of meals served based on arrival time and date into the local jail. Meal times are 0650, 1150, 1550 & 1930. I need the formula to be based on book in date and time through out date and time so that the correct number of meals are billed for. this could span a number of day or several months. I;m not sure if there is any way that this can be done but I would greatly appreciate any help that anyone can provide.

Hi and welcome to the forum

i would suggest you upload a sample work book, (all sensitive data removed), showing what data you are working with, a few examples of what your expected outcome is, and how you arrived at that
To attach a file to your post,
click advanced (next to quick post),
scroll down until you see "manage file",
click that and select "add files" (top right corner).
click "select files" find your file, click "open" click "upload" click 'done" bottom right. click "submit reply"

Once the upload is completed the file name will appear below the input boxes in this window.
You can then close the window to return to the new post screen.