By Pandemonium.Eternaltriumph 2010-05-11 10:56:51
It's dependant on a few things, which ops show up. Some of them "cap out" based on how many people do them. So for the biggest possible list, go there directly after conquest to get the big pickings.
That aside, things such as what areas you control and the BIGGEST influence on which OPs are available depends on what your nations strategy of the week is. So vote, I guess. If your nation is set more on fortifications (which kind of fails for getting areas) you're probably gonna have Steel Resolves all week, and of a higher tier, just as an example. Different strats unlock different OPs.