Not 'wrong' exactly, just reading the agreement from a different perspective... The agreement can also be interpreted so that you only have a minimum of 9 days off at home over 6 roster periods.
What you think the intent of an agreement is, does not necessarily translate to the agreement you had in your mind. If it suits the Company they can enforce these agreements to the letter of the law. I have added the actual clause for everyone to read.
25.1.3 “You will be rostered free of duty at your Home Base for minimum of 9 designated days off in 6 roster periods and 10 rostered days off in 6 roster periods. The minimum number of days off in a roster period for a pilot will be notified to the pilot no later than before the end of the preceding period.”
Please also look at the following clause. (My emphasis)
25.4.5 “If you are at a layover port, or assigned temporary duty away from home base, you will be rostered for days free of duty as required.
We will use our best endeavours to ensure that such days do not detract from your basic entitlement to days off at your home base, except with your consent or at your request. You will be rostered for any days off accumulated under this provision upon return to your home base or where this is not possible, in the next roster period.”
I know of an ex-deputy-chief pilot who would be salivating at these words should they be written into existing mainline certified agreements.