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Understanding CTE losses in WFC3-UVIS has very much been a learning experience. Once it became clear that there were significant losses at the small-electron-packet end comma we realized that we needed more than the strategy that had worked so well for ACSdoublePoint namely comma just measuring the trails found behind the warm pixels (WPs) in the calibration long darks. We devised a strategy that used a combination of short-darks and long-darks. The long-darks allowed us to know the true intensity of each warm pixel comma and the short darks with variable background allowed us to measure electron-survival as a function of background. This new strategy has worked well comma but there are not as many WPs in the short darks as we would like. We experient here with a different approach. We will take the standard 900s long darks with a variety of post-flash levels so that the relative losses-vs-background can be assessed. This approach is not as direct as the short-long approach comma but it may provide more data and it is actually more in-line with what actually gets done for science. Also comma this new approach provides a lot more WPs to study comma which should give us much better resolution on losses as a function of background. The short-dark data taken in the previous calibration cycle has noisy trends for backgrounds between 20e and 100e. This program should remedy that significantly.