Possibility \#3

Possibility #3

When ṃ is followed by l,

ṃ can become l.

e.g. saṃ + lekha > sallekha

This rule is not found in Kaccāyana, but can be found in Rūpasiddhi under (49) vagg’antaṃ vā vagge.

ṃ + l > ll

saṃ	lapati	sallapati	pr. chats together
saṃ	lekha	sallekha	m. erasing, effacing
paṭi + saṃ	līna	paṭisallīna	pp. secluded
puṃ	liṅga	pulliṅga	m. masculine gender