I don't think I've understood this correctly, marked for revision

Rotate Left Accumulator works by rotating the bits in register A. The left significant bit is taken from the (C)arry flag and then most significant bit is moved off to the (C)arry flag. We actually rotate on a 9-bit pattern (8-bit in the register and a 9th bit in the carry flag).

The RLA instruction does a similar job to RR A but does it faster. There are also some differences in which flags will be affected by RRA compared to RR A.