1.1.55 anekAlshitsarvasya

If a substitute consists of multiple letters or the 'it' marker 'sh', replace the entire target. This sutra effectively overrides the {1.1.52: alo'ntyasya} sutra which restricts the substitution to a single letter.

Hence, the affix 'jas' is replaced entirely by 'shI' in sutra {7.1.17: jasaHa shI}. Thereafter, the 'it' marker 'sh' is also elided.