[JMT1985]

The lack of audience is a cost-cutting measure: remember that getting an audience requires a whole range of other costs to be included, such as the need to pay for stewards to make sure only ticketed people entered the studio, security to monitor for suspicious audience members, insurance to cover for any incidents involving audience members, the floor manager needing to keep the audience in check etc. These all mount up over the course of a series, and cutting that out from a production allows them to focus the money on other things instead.

Also, to my understanding, the studio used by Countdown now doesn't support audiences being present in any way at all. If they wanted audiences back, they would have to pay more for a larger studio to support having an audience. In todays' highly inflated society, there's just no scope for Channel 4 to support bringing it back. I wouldn't say no to them having a limited audience for series finals though, then it won't cost as much and will make the final more authentic.

As for number of episodes per day, as confirmed by a contestant who'd appeared on the programme on another website, its 6 a day now with breaks of 2-3 weeks in filming at presumably scripted parts of the year.

Countdown has used Dock10 studios in Salford for many many years, when Yorkshire Television studios mostly closed down (only local news and Emmerdale being made there) and so they initially moved to Granada Studios, before moving into Dock10 when Granada Studios closed. 

Dock10 has large studios which they could use - HQ4 is a studio they used, and probably currently use, which has space for an audience of around 300 - so it is not about the size of studio that is the problem, it seems when Covid hit, this was of course the main reason for having no audience, but when all restrictions were abolished, and life returned to normal, the production seemed to think why waste our time in bringing in an audience again. 

However, with all that saved cash, what else can they spend it on in Countdown, larger salary for Colin, Rachel and Susie? Probably benefits Channel 4's current cost cutting measures.