As we reached the limit of my first extension of the Extensible-E system, Collapsing-E notation (&E), which has the growth rate of the Bachmann-Howard ordinal, I propose to extend the notation in a similar fashion to my previous one. There are many proposals by me, but there will be only one agreed upon extension of the Collapsing-E notation, called "Extended Collapsing-E notation" (x&E), which introduces multiple levels of ampersands, using subscripts (such as &_2, &_3, &_4, etc.), rather than up-arrow notation to ampersands (such as &^^##, &^^&, &^^^#, &{&}#, etc.). In that case, it make the fundamental sequences on multiple levels of ampersands much more contingent!