14yy는 최소회선이 30이네요.
http://www.sktelink.com/os/bu/as/rs/bu_as_rs_collect_call.do
그 밖에 080 역시 2회선이구요.
https://biz.kt.com/html/product/bz_product_com.html?pc=3CBCA0
KT는 브로셔가 디자인 좋군요 ㅠ
https://biz.kt.com/attach/prod/3CBCA0/150693889178300014.pdf