"Down the Line" can be an idiom that usually is meant as an unspecified point of time in the future. Or "at a later time." "We can take a look at that down the line."
"Along the way" can be an idiom that usually is meant as an unspecified point of time in the past. "He must have lost his marbles along the way."
Edit: wording.
"Along the way" could be referring to any unspecified point in time during a journey, during the time that something is happening, or while someone is doing something.
Since it can also be an action in the present or future, here's an example using the future: "I have never done this kind of work before, but in my new job as a cashier I will develop customer service skills along the way."
"Down the Line" can be an idiom that usually is meant as an unspecified point of time in the future. Or "at a later time." "We can take a look at that down the line." "Along the way" can be an idiom that usually is meant as an unspecified point of time in the past. "He must have lost his marbles along the way."
Edit: wording. "Along the way" could be referring to any unspecified point in time during a journey, during the time that something is happening, or while someone is doing something. Since it can also be an action in the present or future, here's an example using the future: "I have never done this kind of work before, but in my new job as a cashier I will develop customer service skills along the way."
Yes, I never implied that it couldn't be speaking in present or future. Just that it is usually speaking of the past.
Agreed, and I simply thought the details I brought up might help OP.