It is generally possible to print on a larger format without any significant loss of quality, as long as the enlargement is no more than twice as large. ﻿
For example, taking a 24" x 36" plan and enlarging it to 36" x 48" would be possible.
However, taking an 11" x 17" plan and enlarging it to 36" x 48" would be risky. ﻿
As the enlargement takes place directly in the machine, we don't see the result of the enlargement until it's printed. It's always best to ask the person who designed the plan to provide it in the desired format for printing.