After a longer break, the right hind hits the ground, followed closely by the right front. The lateral 2-leg support phase is clearly longer than the diagonal support phase. The time interval between the lateral pair of legs hitting the ground is longer than break between the diagonal pair. The scale below shows how there is actually a continuum between pace at the one extreme, and trot at the other. The horse can shift smoothly between these extremes.
Some horses shift towards the canter when at the tolt.
The horse can roll to either the right or the left side, the same as it can canter with a right or left lead. The horse basically steps evenly in the back, while cantering in the front. Cantering on the right lead, the left hind foot is followed by the diagonal pair of the right hind and left front feet. The right front foot then reaches forward. Now, when the tolting horse rolls toward the right, the right hind foot follows the left front foot very closely, with a longer break before the next foot, the front right.