The mechanism that does lower a bill is the assessment itself. If the Board of Revision agrees an assessment is too high relative to comparable Saskatoon sales, or corrects a factual error in the city's property record, the tax bill drops because the number it is calculated from drops, and any owner can file that appeal, not only seniors.
Confusing income supports with tax breaks is the common mistake here. Provincial programs like the Saskatchewan Seniors Income Plan help with living costs generally, but they are paid to the person, not applied against a specific address's tax bill, so they never show up as a line item on a City of Saskatoon notice.
A senior who feels the tax bill has become unaffordable relative to the home's real value is often better served by comparing what the home would sell for against what it costs to hold. Get your hand-reviewed valuation from Joel Dyck.