This is the first time in over 30 years that our team has made it to the champion finals.
If I omit the preposition "in", will there be any change in meaning of that sentence? Because, I think "over" in this sentence neans "during", so there is no need to use extra "in" before "over".
In the original sentence, "over" means "more than", not "during". If you remove "in", then "over" would have to be interpreted as something like "during", so the meaning would change, though the resulting sentence is not tremendously natural. Normally we say "the first time in 30 years" rather than "the first time over 30 years".
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In the original sentence, "over" means "more than", not "during". If you remove "in", then "over" would have to be interpreted as something like "during", so the meaning would change, though the resulting sentence is not tremendously natural. Normally we say "the first time in 30 years" rather than "the first time over 30 years".