Does the monthly Site check page limit vary by plan?

It varies by plan.

The monthly Site check page limits for each plan are:

・30-Day Free Trial: 30 pages
・Light 10: 150 pages
・Light 30: 500 pages
・Light ∞: 1,000 pages
・Standard 10: 1,500 pages
・Standard 30: 5,000 pages
・Standard ∞: 10,000 pages