It could be a dangerous time of year in Ontario. Truck drivers are driving around half loaded.
The half load restriction is put into effect to save the wear and tear on the roads this time each year in Ontario as the thawing ground is less able to take the full weight of heavier traffic until it dries up and hardens later in the spring
Wallers may not be able to get enough stone delivered to the site during this time and the price that they quoted to the client for materials may not reflect the extra half loads that will need to be delivered.
Planning ahead is always difficult but to have all your stone delivered to the job before half load season begins is the best answer.