The army probably wants 1,000 tanks, that's for sure. But I think that after the first batch of 250 Altay tanks, the rest of the orders will wait for the Altay T3 (or will be decided after the T3 roadmap becomes clearer). In the meantime, they seem to want to make do with Altay and upgraded tanks.
With these announced timelines of production and costs involved, we will never have 1000 modern/modernized tanks in the next 40 years unless someone else bankrolls us. Economies of scale don't work here at all. Army is not just being funded less, it's also being downsized since cold war ended. We don't currently have a force structure to operate 1000 modern tanks that require higher rank NCOs and professional soldiers.
TAF wants to replace all tanks in the inventory. I have no doubt for new purchases after the first batch is delivered. Big armies like us gives almost equal budgets to all forces as possible unless it has a special condition like the UK. And when equal budgets are given to the forces, it's easy to understand how big is each forces if you know at least one of them. You can pair MBT's with fighter jets, IFV and other support vehicles with helis and air-transport vehicles. ~200 Kaan's ≈ ~2000 Altay's. ~x T-70's ≈ ~10x Pars Alpha's etc. Ofc these are not any type of certain numbers. Just rough guesses.
And don't forget our army is managing the highest budget since the republic.
So there's money to produce more Altay's. And there's armies will. This is why I have no doubt for 1000+ Altay's in the next decade or so.