You can often have positive actions that would lead you to believe a score increase must be forthcoming. However, it is not your credit report alone that determines your FICO score. FairIsaac has approx. ten different algorithms that they use to generate your consumer score, and many others that are purchased by industry-specific lendors, such as auto or mortgage lendors. There is no single algorithm that is used, and thus often what appear to be illogical scoring changes result from a shift in the use of a new algorithm to generate your score.. Which algorithm is used to generate your current score depends upon the category group you fall in that best compares you with similar consumers. These are often called scoring buckets on this forum.
I have also seen published articles on different sites stating that the FICO algorithm, even in individual buckets, is adjusted periodicaly as they assess risk factor changes within the population. One factor I have seen mentioned by credit analysts is the shifting view on the risk factor based on the number of open CCs, as consumer trends and habits have changed significantly due to agressive actions by CCCs to solicit new acoounts through the offer of low introductory rates.
Bottom line is, dont expect that the agorithm used to generate your credit score last month will be the same one used to generate it this, or next, month.