Some components of teleodynamics might be pertinent to your intended changes to the present tense of the timeline.

Switching from the geocentric to the heliocentric model of the solar system does not change the direction that the planets move, it models the very same movement in a different way. — Metaphysician Undercover

Consider: the earth with respect to the sun and the sun with respect to the earth when the sun orbits the earth. In the limited context of this relationship, is the earth stationary and the sun mobile?

Consider: the sun with respect to the earth and the earth with respect to the sun when the earth orbits the sun. In the limited context of this relationship, is the sun stationary and the earth mobile?

In making a comparison of the two above considerations, do you say the two considerations model the very same movement in a different way?

The first statement of "when the sun orbits the earth", is what we know as the rotation of the earth on its axis. The second statement "the earth orbits the sun", is what we know as the earth revolving around the sun. These two do not model the same motion.

What we model as "the rotation of the earth" is the same motion as what you described as "when the sun orbits the earth". If we know the distance between the earth and sun, and assume the earth to be a point at the centre of a circular orbit, we could calculate the speed at which the sun orbits the earth, in that model in which the sun orbits the earth.

Time is unidirectional, future to past. This is an activity of the world, what we know as the future becoming the past, The day named as "tomorrow" becomes the day named as "yesterday" through this activity, this process of the future becoming the past. — Metaphysician Undercover

Jan 5 is in the future before it is in the past. The flow of time has that portion of time named as Jan 5, in the future prior to it being in the past. — Metaphysician Undercover

This process of the future becoming the past has the arrow of time moving in which direction: a) the events of Jan 5 change into the events of Jan 4; b) the events of Jan 4 change into the events of Jan 5?

Since you say, “time is unidirectional, future to past,” and also you say, “the day named as tomorrow becomes the day named as ‘yesterday,’” logically we have to conclude the arrow of time moves from Jan 5 to Jan 4. Entailed in this is the logical necessity that you become a day younger as the arrow of time continues to move from future to past.

Have you ever grown a day younger in your life? Speaking more dramatically, can you remember being ten years older than you are now?

Does today become tomorrow, or yesterday? Your answer speaks to your perception of the direction of the arrow of time.

This process of the future becoming the past has the arrow of time moving in which direction: a) the events of Jan 5 change into the events of Jan 4; b) the events of Jan 4 change into the events of Jan 5? — ucarr

I don't see what you are asking. The events of Jan 4 are the events of Jan 4, and the events of Jan 5 are the events of Jan 5. One does not become the other. However, the time marked by, or referred to as "Jan 4", itself moves from being in the future to being in the past, as does the time referred to as "Jan 5".

The difference is that in my model, time itself is assigned substantial existence, as something. What we know as "the passing of time", which is the process by which the time indicated as "Jan 5" changes from being in the future to being in the past, is reified, understood to be something real, a real process. This "something" can be understood as the cause of all events. Time passing is not the events, nor is it an event, but it is the cause of events. And, we order events as past events being prior to future events, due to the way that events are observed by us through sensation. However, when we consider time on its own, as something which can be marked with indicators such as dates, then we understand that any indicated time, is in the future before it is in the past, like the example shows.

Here's another way of looking at it, which may or may not help you to understand. Imagine that there was a start to time, time started, there was a beginning to time. At the point when time began, there was future, but no past, because no time had passed yet, but there was time about to pass. And, as time passes, there becomes more and more past, and less and less future. Imagine a wind-up toy, fully wound, and ready to go. The process of its unwinding is fully in the future, but as it unwinds, it goes into the past. This demonstrates that future is prior to past.

Since you say, “time is unidirectional, future to past,” and also you say, “the day named as tomorrow becomes the day named as ‘yesterday,’” logically we have to conclude the arrow of time moves from Jan 5 to Jan 4. — ucarr

Why do you say this? If "Jan 4", and "Jan 5" referred to events, we'd say that Jan 4 occurs before Jan 5. But these do not refer to events, they refer to dates in time. If we made a timeline, based on our empirical observation of events, we'd see that the events of Jan 4 are prior in time, to the events of Jan 5, and we might be tempted to model "the flow of time" in that direction. However, this is because we are mapping the dates as events which occur. A true analysis shows that both Jan 4, and Jan 5. are in the future before they are in the past, so regardless of the order that these dates occur to us as events, the future part of time is prior to the past part of time.

Your conclusion doesn't seem to be valid, and I do not know how you derive it. The arrow of time has it that the day named as "Jan 4" was in the future before it was in the past, as is the case with the day named as "Jan 5". Now, today, the day named as "Jan 9" is in the future, but soon it will be in the past.

Now if we look at "Jan 9" as an event, instead of as a date, we will say that this event occurs after Jan 8 occurs, and we will represent this with a number line of sorts, showing that order. But according to my explanation, that number line represents the occurrence of events, it does not represent the passing of time.