Exactly! We use pret. imperfecto to talk about the situation in the past and we use the present form to contrast with the new situation.
Here are some examples:
- Antes, iba al gimnasio 4 veces a la semana; ahora, voy al gimnasio 2 veces porque no tengo mucho tiempo.
- Antes, escuchaba música en CD y ahora escucho música en Spotify
Would you like to practice it? You can find me at https://teach.italki.com/teacher/1296254