Use an XMLHttpRequest object in Javascript to download the page that you need and then use a regular expression to parse out the dates. It seems that the dates all have a fixed format:
<b>Mon Day Hr:Min UTC+4</b>
so it should be easy to write the regular expression for this. I don't know the exact Javascript Regex format but here's the .NET equivalent, it should be easy to tweak this to Javascript - hope this helps:
<b>(?<date>(?:Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec) [0-9]{2} [0-9]{2}:[0-9]{2}) UTC[+-][0-9]+</b>
This finds all date fields in the page - once you have the date fields, each Regex match will have a sub-group named date
that contains the actual date part.
If you go to this page: .NET Regex tester you can test the above expression to see how it returns the dates - just copy & paste your page's source with the dates. As I said, this is for .NET, not for Javascript but the differences are not terribly big.