Braiding Time

It's been a while, but I've done another writing exercise to post. Again, this is from the Now Write! collection. This exercise is helpful in deepening and authenticating character, exploring in particular how a character thinks. It can also be useful in learning to weave exposition deftly into a story.
   We all live within a complex weave of three strands of time: the present, the past, and the future. At any given moment our minds are shifting from the focus of the moment to what we anticipate might come next, to incidents from the recent or deep past that still preoccupy us. It is the unraveling of a character's relationship to all three elements of time, the writer becomes more deeply acquainted with his or her character.
   So, the exercise involves choosing a character to work with, and write four paragraphs. The first paragraph, the character must be involved in some present ongoing action. In the second paragraph, keeping the character still engaged in the ongoing activity, the character is imaging what s/he will do in the future. In the third paragraph, still using the present activity as a starting point, write about something from the past that the ongoing action is prompting the character to remember. Finally, the fourth and final paragraph, use the elements of forward-looking and backward-looking as the character continues with, or completes, the action. Working on making the transitions between time frames feel continuous and smooth.
   Here's my attempt:
The sun dropped below the rolling peaks of the hills as they descended into the valley. Relieved to no longer be squinting into the blinding globe, Harry began to take in the familiar surrounds. The drooping gums, the dry rocky creekbed, and the narrow track over which he had rode many times. His dog jogged along behind, mindful of rocks flicked up by hooves, ears flickering backwards and forwards alert for all sounds in the bush.
   Bill shifting in his saddle, easing himself into a new position, and allowing for the effects of his weight on his horse's progress down hill. He lead a second horse, carrying basic provisions and the mail that he had collected from Talbotville that morning. He was visiting the new manager of Wonangatta before heading to his own hut the following day. He had met Jim before, at various cattle and horse sales, but hoped this visit would cement an understand between the neighbouring properties.
   As the open plains of the valley spread out before him, he restrained himself from arching to look for the homestead. Many times had he descended this path, longing to catch a glimpse of Margaret before she knew he was there. Her natural, unobserved movements about the farm had caused him to yearn for her in those quiet moments. As soon as she knew he was present, or as soon as her family members were around, her self-conscious, brusque behaviour returned, determined to keep everyone at arm's length.
   But the family had left the homestead, the original settlers, his own father included, all long dead. Wonangatta had stood empty these last months, the furniture all covered in linen, until the rights had been sold to men from Mansfield. Jim's appointment as manager was the first news uttered from anyone's mouth, after appropriate greetings, in Talbotville that morning. Harry hoped that he was the first to call on the new manager, so that he could convey to Jim just how things should be.