surely changes in the BTC price along the way will both affect how many BTC we are able to accumulate in a certain period of time and how it is valued (in dollars) at various points in the journey.
Yes you are correct, the price of Bitcoin can change and that determines how many Bitcoins we can collect in a given period and what its value (in dollars) will be at different times along the way. The amount of Bitcoin we collect and its dollar value in a given period may vary, depending on changes in the price of Bitcoin. If the price of bitcoin increases, we can collect more bitcoins and its dollar value increases. Conversely, if the value of Bitcoin falls, we will collect fewer Bitcoins and the dollar value of the collection will decrease. Hence, the stability of Bitcoin price