Could the Orlan-MK use an umbilical if need be?

Question

According to the Wikipedia article on the Orlan space suit, all models of the suit after and including the Orlan-DM were designed to be self-sustaining:

The first Orlan suits were attached to the spacecraft by an umbilical tether that supplied power and communications links. The Orlan-DM, and all models since, were designed to be self-sustaining.

                                                                   ^{A spacewalker in an Orlan-DMA suit.}

However, it seems that there are many advantages to using an umbilical - you could stay outside much longer, for one. Could the suit use an umbilical if needed?

Answer 1

In the book "Russian Spacesuits" by Isaac Abramov, Isaak Pavlovich Abramov, Ingemar Skoog (ISBN-13: 978-1852337322, Google books preview), there is a page comparing the different Orlan models on page 319. It says "umbilical" for the older models, and "(umbilical)" in parentheses for the newer models. So this probably means that they can still be connected to an umbilical, probably for recharging on board of the ISS.

However, just as with the older models, this cannot be used to extend the duration of the EVA, as it provides only power and communications. It doesn't extend the capacity of the suit for oxygen, fresh water, carbon dioxide removal, etc.