PMM already answered that for you. No other date apart from date of arrival in Canada- you're given 6 months allowed visit.
I have multiple entry canadian visitor visa (V1) vaild for 1 year. When i entered at canada IO did not tell me how long i can stay. In my passport in one of the page there is a stamp by IO and this is how it looks It is a black square box and at the top it is written "Canadian immigration and below that today's date is stamped" . Just curious how someone should know how long he/she can stay?