liʾayyi (Q77:12) is regularly spelled لايى, rather than لاى. This presumably representing loss of the hamzah: /li-yayy/. This is often missed in text editions of manuscripts. You also see it regularly spelled this way for biʾayyi بايى and fa-bi-ʾayyi فبايى. 
With my new copy of an amazing and brand new edition of the Našr al-Qirāʾāt al-ʿašr (thanks @therealsidky!) I have no found some confirmation of such a reading. al-ʾAṣbahānī (transmitter of Warš) reads fa-bi-ʾayyi as [fabiyayyi] whenever it occurs.
There is disagreement among the transmitters whether bi-ʾayyi (Q31:34) and bi-ʾayyi-kum (Q68:6) (spelled باييكم even in the Cairo edition!) are read with the loss of the hamzah as well, but at least some transmissions say so. No word on li-ʾayyi, however.
ʾayyi is not spelled like this when it is not preceded by bi- or li-, e.g. min ʾayyi šayʾ (Q80:18).
