Not really sure where to put this question. I was accepted but now want to switch the duration of my masters

[sleepdeprived777]

I was accepted by the Central European University (CEU) in Vienna, with a generous stipend and a huge tuition waiver. However, with the pandemic, I cannot attend it offline for at least 1 semester. Hence, I want to switch from 1-year degree into a 2 year. More than that, it seems way less stressful and will allow me to experience Europe. What is the best plan to address this question to the department?
Has anyone else undergone a similar process?