YOU SAID:

I stayed up until 1 a.m. last night

INTO JAPANESE

昨夜は午前1時まで起きていた

BACK INTO ENGLISH

i was up till 1am last night

INTO JAPANESE

昨夜は午前1時まで起きていた

BACK INTO ENGLISH

I was up until 1am last night

INTO JAPANESE

昨夜は1時まで起きていた

BACK INTO ENGLISH

i was up till 1am last night

INTO JAPANESE

昨夜は午前1時まで起きていた

BACK INTO ENGLISH

i was up till 1am last night