I’m PADI Rescue Diver level. Just wondering if it can be learnt in a day or if it’s a more involved one week course, for example. Thanks for your time
A well prepared wreck course can be done in a weekend with a little pre course preparation. It’s not a single day thing as a rule since the task loading and the scenarios can be mentally draining. Especially when you’re lead diver. You’re a rescue, so you’ve got the prerequisite of AOW already. That’s no issue. You’ll want to get your gear in order before taking the course, since you will be doing penetration into an overhead. That means some redundancy. You’ll be required to own a back up light as well as primary and owning your own reel would be a good idea as well, since you may not be able to borrow one. Having two…even better but not required.
A good instructor will do everything they can to make your dives as miserable as possible. 
They’ll silt you out to zero viz and have you navigate inside a wreck. Safety divers will be there, no worries but you won’t see them. They may even break your line to see how you handle it. Tons of scenarios. They may even "kidnap" your buddy in a silt out and see what you do. See what I mean about task loading? They’ll also do their best to improve your buoyancy skills ( I recommend taking peak buoyancy specialty before you do wreck, personally). The less you touch, the better your dive. Getting hung up on electrical wiring by your tank valve sucks. Been there due to a momentary lapse of judgment and and few extra jelly donuts that morning.
It is a fun course though and your graduation dive will be a blast. You’ll also get to see what’s on the inside and not just be happy with exterior superstructure or swim throughs.
A well prepared wreck course can be done in a weekend with a little pre course preparation. It’s not a single day thing as a rule since the task loading and the scenarios can be mentally draining. Especially when you’re lead diver. You’re a rescue, so you’ve got the prerequisite of AOW already. That’s no issue. You’ll want to get your gear in order before taking the course, since you will be doing penetration into an overhead. That means some redundancy. You’ll be required to own a back up light as well as primary and owning your own reel would be a good idea as well, since you may not be able to borrow one. Having two…even better but not required.
They’ll silt you out to zero viz and have you navigate inside a wreck. Safety divers will be there, no worries but you won’t see them. They may even break your line to see how you handle it. Tons of scenarios. They may even "kidnap" your buddy in a silt out and see what you do. See what I mean about task loading? They’ll also do their best to improve your buoyancy skills ( I recommend taking peak buoyancy specialty before you do wreck, personally). The less you touch, the better your dive. Getting hung up on electrical wiring by your tank valve sucks. Been there due to a momentary lapse of judgment and and few extra jelly donuts that morning.
A good instructor will do everything they can to make your dives as miserable as possible.
It is a fun course though and your graduation dive will be a blast. You’ll also get to see what’s on the inside and not just be happy with exterior superstructure or swim throughs.
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