Calculation of GWV service cars at 2 workplaces

Hello to the round, I would like to use your knowledge. The following case (current workplace A): Service car list price 30,000 Euro // 100 km easy way to work. 300 Euro (1 % of the gross list price ) + 900 Euro GWV (0.03 %) = 1,200 Euro Controlling company car. Tax-free amount of 5.550 registered. Future case (job B): Care of another branch. 50 km from the place of residence. How is calculated here? Which workplace counts (A or B)? I is it relevant how often / how long do I work at workplace A or B on the day / week / month? And no, it’s not about the question whether it makes any sense to commute 100 km daily (one way)… Thank you very much!