Do you use the iPad in deep cold? I'd normally just take my laptop but it's not going to respond well to be frozen for many hours at a time time, for several days and then there's the issue with the battery, which likely wouldn't appreciate being charged before the laptop is brought to above freezing temps....I always travel with an iPad Pro and carry at least two XQD/CFE readers with me, with integrated USB-C.
You might consider using in-body copy to an SD (if you have a Z8, e.g.), then copy that SD to a portable drive. I have a 3T WD My Passport drive that has a built-in SD 3.0 reader. Mine is an earlier version (and cheaper) that isn’t SSD, but it works the same.