FF55 (rHDMA5) contradicts Pan Docs

[nummacway]

Pan Docs say:

Reading from Register FF55 [...], a value of $FF indicates that the transfer has completed.

and

Reading Bit 7 of FF55 can be used to confirm if the DMA transfer is active (1=Not Active, 0=Active).

hardware.inc says bit 7 is 0 when not busy:

def B_VDMA_LEN_BUSY equ 7 ; on read: is a VRAM DMA active?
    def VDMA_LEN_BUSY equ 1 << B_VDMA_LEN_BUSY
        def VDMA_LEN_NO  equ 0 << B_VDMA_LEN_BUSY
        def VDMA_LEN_YES equ 1 << B_VDMA_LEN_BUSY