Sorry, my original wording was wrong. It is as follows BOLD and Italics added for viewing ease):

"To the maximum extent possible, blocks of five (5) consecutive
days off in domicile. In lieu of the above, to the maximum extent
possible, no less than four (4) consecutive days off in domicile,
except relief lines may contain blocks of less than four (4)
consecutive days off in domicile on the first three and last three
days of the month."

So when they "deviated" from the 4-5 days, they really weren't breaking the contract. But the precedent was there...
IMHO