Hi Vic,
I'm assuming your are asking about residential mortgages. If you were originally qualified on a 35 or 40 year amortization, it is my understanding that lenders will not be reducing the amortization at renewal. As long as you are not making any material change to the mortgage, then the original amortization (less the time gone by) will apply.
In most cases lenders will offer you rates less than the market, but you can negotiate lower. If you transfer the mortgage to a new lender it is my understanding that they lender can honour the original amortization provided there is no material change to the mortgage.