This is where hrTSS is super helpful. I would just use whatever your hrTSS is giving you for that day on the bike and not adjust it any further. Since hrTSS is the same metric for hiking, biking, running, skiing ect… you can use it for different sports and get accurate data. The only time you need to adjust TSS is for strength training, weighted pack hikes or days you are getting in a lot of vertical ft.
Does that make sense?