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Based on my experience, the only portion of the BJCP Guidelines I would ignore is OG/FG, but even then, I've seen some people say that they've had questions reference those values.
There will be questions that specifically reference a beer with a specific range of SRM and ABV, with no additional information, and there will be some that require you to know specific points in the description that wouldn't apply to any other beers.
In addition, you'll see at least one long answer question requiring you to pretty much regurgitate all the information you can on a specific style, so knowing as much about as many styles as you can will be a massive help there.
I did three things to prepare for this, which I would use alongside trying as many varieties of the styles as I could.
I made a small laminated card that had style names and all the quantitative values and I would study as I drank beers, or whenever I had a few minutes. This gave me just something I could quickly check and put away.
I also found an app that allowed me to verify style information on the go, on Android it's at https://play.google.com/store/apps/details?id=io.github.rlshep.bjcp2015beerstyles
Then to quiz myself, I used a website that can quiz you or just give information. https://bjcp.thegremlyn.com
I'm not sure any style is as broadly define as IPA to be honest. East Coast vs. West Coast are two noticeable differences. Within the broader Brown Ale style there's English and American, which are noticeably different, but the contrast isn't as stark as it is in IPA.
Have you looked over the BJCP guidelines? A lot of people don't really care about them, and I'm not mega reverent to them either, but they do provide a good guide of what to look for in taste and aroma and provide some solid examples for the style. Though they don't recognize differences like in East Coast vs. West Coast vs. New England IPAs.
Here's a link to a handy app on Android
I don't know any apps on iOS, but I know there are some.
For actual recommendations...
West Coast: Alpine Duet, Stone IPA, Green Flash West Coast IPA or Soul Style
East Coast: Dogfish Head 60 min (90 is great but it's more of a double IPA), Bell's Two-Hearted, Ithaca Flower Power
Edit: formatting
Beer Style Compendium is pretty good.
https://play.google.com/store/apps/details?id=io.github.rlshep.bjcp2015beerstyles