Actually, according to your picture, it seems that your vehicles might not be vintaged after all, and if they are not vintaged, then the solution would be very easy: Just define the scenario-specific input share projections in a regular scenario file, using a TFM_INS / TFM_INS-TS table.
But anyway, you seem to have three types of fuel blends: gas, diesel, and gasoline blend. So, you could introduce a process for making each of these blends, with the corresponding two inputs and one blended output fuel. Then just replace those vehicle input fuels representing the blending components with the corresponding blended fuel. The blending processes would be something like:
● Gas blending: Inputs: TRABG, TRANG ; Output: TRAGASBL
● Diesel blending: Inputs: TRADS, TRABIO ; Output: TRADSTBL
● Gasoline blending: Inputs: TRAGS, TRAETH ; Output: TRAGSLBL
Then it would be straightforward to define the current and future blending shares for these three blending processes. According to my experience, this is a very common way of modeling such blended road transport fuels. The small drawback in this approach is that the GHG emissions would need to be accounted at the blending processes, but usually that is not any significant issue. The advantages are the simpler vehicle processes, and easiness of adding some additional blending components (e.g. electrofuels) as well.
From your picture, it also seems that your blending shares may be all fixed shares. If that would be sufficient, then there is also a way of defining non-vintaged share projections at the vehicle processes, by using process parameters. However, if fixed shares are not sufficient but the shares should be flexible, user constraints could indeed always be used for the modeling of non-vintaged blending shares at vintaged vehicle technologies, when such are deemed necessary. But for now, as there are several aspects of your modeling approach I don't know, I am not going to try giving detailed instructions for using these two other options right now. If you can clarify the questions above (are the processes actually vintaged, do you need other than fixed shares, do you in fact need blending at the vehicle technologies?), I could try and give some more help later, if needed.
But anyway, you seem to have three types of fuel blends: gas, diesel, and gasoline blend. So, you could introduce a process for making each of these blends, with the corresponding two inputs and one blended output fuel. Then just replace those vehicle input fuels representing the blending components with the corresponding blended fuel. The blending processes would be something like:
● Gas blending: Inputs: TRABG, TRANG ; Output: TRAGASBL
● Diesel blending: Inputs: TRADS, TRABIO ; Output: TRADSTBL
● Gasoline blending: Inputs: TRAGS, TRAETH ; Output: TRAGSLBL
Then it would be straightforward to define the current and future blending shares for these three blending processes. According to my experience, this is a very common way of modeling such blended road transport fuels. The small drawback in this approach is that the GHG emissions would need to be accounted at the blending processes, but usually that is not any significant issue. The advantages are the simpler vehicle processes, and easiness of adding some additional blending components (e.g. electrofuels) as well.
From your picture, it also seems that your blending shares may be all fixed shares. If that would be sufficient, then there is also a way of defining non-vintaged share projections at the vehicle processes, by using process parameters. However, if fixed shares are not sufficient but the shares should be flexible, user constraints could indeed always be used for the modeling of non-vintaged blending shares at vintaged vehicle technologies, when such are deemed necessary. But for now, as there are several aspects of your modeling approach I don't know, I am not going to try giving detailed instructions for using these two other options right now. If you can clarify the questions above (are the processes actually vintaged, do you need other than fixed shares, do you in fact need blending at the vehicle technologies?), I could try and give some more help later, if needed.