I typically offer 1 year of those types of changes (refered to as miniscule in the contract)
stuff like phone number, address, main contact email, etc.
In my 7 years of doing it, i think i've made maybe 6 of those miniscule changes.
Businesses don't change their phone number or address very often.
I even stretch and make some less miniscule changes for good clients - like adding award graphics every year when they win the cities "Best Of" list.