19:16 Well, even before this crisis, it's inherent in our business that we are always looking to diversify our sources, the supply from reading our SEC filings, of course, we have major supply arrangements with Orano, the French enricher. We have other arrangements besides and we are continually refreshing and updating that, obviously more recently with the events in Ukraine, we have doubled down on those efforts and continued to look at ways to move things around and we have people who are very good at, it’s a very diversified market with lots of pockets of different parts of the fuel components and so forth. And we're just continuing to do that as much as we can. 20:08 The other thing of course, we have done is, as you've seen over many quarters to continue to strengthen the balance sheet, including building up good cushion of cash. So, if there are disruptions that are requiring more cash or whatever to achieve the kind of diversification and mitigation that we need to, we have some of that as well. 20:33 So, we're just in a continual mode of continuing to diversify and find alternatives, but obviously the longer a disruption would go on, the more challenging that would become because, as, again, I'm sure you know, Russia accounts, and I said this in my opening remarks, 46% of world capacity and it's not like oil where you can just start pumping, it's not like a genie that you have a massive amount of enrichment pop-out onto the market when you rub a bottle or clap your hands. 21:08 So, it's a challenge not only for Centrus, it's a challenge for U.S utilities, it's a challenge for the whole industry. If 46%, it’s just common sense of world enrichment capacity is removed from the global market, there's just not enough enrichment left to power the existing fleet of world reactors worldwide. So, it's – we are a small part of a very large puzzle.