fresh off the heels of just getting comfortable with ~는 대로 I come to find out that it it isn't all that common. In fact, there's a whole nother grammar point that does the exact same thing, ~자마자. So, what's the difference?
~는 대로 is used mostly for things in the future (미래)
~자마자 can be used for all three tenses (과거, 현재, 미래)So, although 미사를 끝나는 대로 어머님께 전화했어요 (Right after Mass ended, I called mom) is grammatically correct and will be understood, it might be more natural to say 미사를 끝나자마자 어머님께 전화했어요 since it was in the past.
Saying 수업을 끝나자마 밥 먹으러 가자! (right after class is over, let's go get some food) is also fine, but sticking with 수업을 끝는 대로 밥 먹으러 가자 might be better. Keep in mind that they indeed mean the same thing but like my teacher pointed out, 는 대로 might not be as common. How she drew it is on the bottom of this post.
화장실을 사용하자마 손을 씻어요
Right after I use the bathroom, I wash my hands.
집에 도착 하자마자 배달 음식을 주문해요
Right after I come home, I order delivery.
새 책을 사자마자 책 안에 내 이름과 구입한 날짜를 써요
Right after I buy a new book, I write my name and purchase date inside.
월급을 받자마자 거의 모든 돈을 와이프에게 줘요.
Right after I get paid, I give almost all my money to my wife.
버스를 타자마자 멀미가 나요
Right after I ride a bus, I get motion sickness.
밥을 다 먹자마자 달콤한 것이 먹고 싶어요.
Right after I finish a meal, I want to eat something sweet.
나쁜말을 하자마자 죄책감이 들어요.
Right after I say bad words, I feel guilty.