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Cheddar, 102 96 79 71 bytes
17 bytes thanks to Downgoat, and inspiration for 8 more.
"A"+(2@"27+@"(25|>1)).bytes.map(i->(65@"(65+i)+(65@"(64+i)).rev)).vfuse
The fact that strings can concatenate but not arrays means that I would have to convert the two ranges to strings, concatenate, and then...