"... in good time" is the correct answer. There are many excellent online tools which can help you find answers. frequency information - google ngram of "in good time" and "at good time" https://books.google.com/ngrams/graph?content=in+good+time%2C+at+good+time&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t1%3B%2Cin%20good%20time%3B%2Cc0%3B.t1%3B%2Cat%20good%20time%3B%2Cc0 explanations google in good time google at good time Oxford Learner's Dictionaries https://www.oxfordlearnersdictionaries.com/definition/english/time_1?q=time in time (for something/to do something) ​ not late; with enough time to be able to do something Will we be in time for the six o'clock train? The ambulance got there just in time (= to save somebody's life).

1. Use "in", though I would say "just in time ..." 2. Yes, that is correct.

I think that you are right