The latest advancements on the subject were presented in 2018 by Luschchekina and Masson. The researchers conclude that at least one excess proton should be present in the extended active site, and this proton could potentially shuttle between Glu197 and Glu441. Here we show that for classical molecular dynamics (MD) the consideration of this proton is still not enough to achieve adequate results. Untangling the issue, we build upon the results of Luschchekina and Masson in multiple directions. We affirm their findings in a dynamical modeling regime with QM/MM MD applied to each and every potential protonation pattern of OP-inhibited BChE extended active site. We then extend the finding to hAChE to present an extensive comparative study. We show how the balance between protonation states depends on the stage of the reaction or inhibition and how it differs between hBChE and hAChE. A crucial role of the position 322 (311 in hAChE) in this process is explained. Barriers of proton transfer in some cases vouch for the existence of a pair of conjugated low-barrier hydrogen bonds (LBHBs), a unique feature that has not been previously reported for any protein. Therefore, cholinesterases feature a unique structure of their extended active site, which is hard to reproduce in classical MD, and we conclude our work by advocating for the development of ad hoc restraint schemes for such studies.