Here is a possible solution if you can figure out on how to make the global work. 

Above global output last build time.  Now if it can be edited so it will display Last Build Time + 8 or 10 or 12 hours as set in the global (without breaking days/month/year), it would be 110% perfect solution. 

So in final output the counter will only show 10 : mm : ss .. till next build. 

I know what you mean about looking up for countdown script.  I looked at quite a few myself, however either most of them were bulky and had tons of codes or with very little feature.  The one I have setup right now only has few lines of code and seems to work like a charm for certain fixed counter, but when it comes to setting up new time, I didn't found anything even remotely closed. 

That's an interesting idea, and I suppose using combination of if/elseif I should be able to setup something for this function. 

This global would give an exact output, and using if/elseif conditions it might also be possible to make it work, however it seems like code will get bit messy to keep date, month and year current, like only 10 hours behind next build date or trying to display next build time exactly 12 hours after current build date..

This is an optional but highly desired feature for the site, however the more I think of it, the more messy it seems. 

Yeah, as I said - even once a day is almost overkill (it all really depends on how many reviews / new listings you validate each day - if you are not validating more than a couple of listings/reviews a day, I'd just set it up to run maybe once every 1 day, or even every 2 days. 

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