Sorry, there was some misinterpretation of question i guess.
Limit for exclusion from applicability of rotation was increased from 20 crore to 50 crore on 22nd June 2017 which was applicable from May 18 exams. This doubt was asked repeatedly during May 18 and Nov 18 exams, so i was habitual of giving this as answer.
Limit for exclusion from ceiling limit of 20 never changed, it is 100 crore for private company , since introduction from 2015 it has remained same , so there is no question of any amendment.
As there were many doubts, just looking at 20 in question , i thought doubt is regarding applicability of rotation.
Please make a note of above