cc65: another unexpected error with .bank directive

minimal example:

.define BASEADDRESS         $123456
.define BANKNR              $12

; this works always
;offset = (BASEADDRESS + (BANKNR * $1000))

; none of these work with the second LDA
offset = (BASEADDRESS + ((<.bank(banksym)) * $1000))
;offset = (BASEADDRESS + (<(.bank(banksym) * $1000)))
;offset = (BASEADDRESS + ((.bank(banksym) * $1000)&$ffff))

banksym: 

        lda #<(offset >> 0) & $ff       ; working

        lda #(offset >> 0) & $ff        ; range error ?

in the real code, offset will be a 25 bit address. there are 4 LDA like above shifting by 0/8/16/24 and then masking with $ff. this works fine with the first expression that does not use .bank - as soon as i use .bank in it, i need to prefix the shift with a < operator as in the example, else i get a range error. i dont quite understand why, as the & $ff should reduce the expression to 8 bit either way. i’d expect both to work, regardless of the .bank directive being used.