Very possible.
Reserve Line reconstruction is described in 7.G.3.d. Subparagraph i. says that the reconstructed line will contain all of the original R-days that are not in conflict with the Vacation and buffers (unless the number of R-days plus vacation days exceeds the number of R-days for the month (19 in July)). IN other words, if the 14-day footprint of vacation, extension and buffers knocks out 14 R-days, you'll need to add back 4 R-days to achieve a total of 19 Vacation Days plus R-days. But if you knock out fewer than 10 R-days, then you'll need to remove all but 9 of the remaining R-days. Either way you'll end up with 7 days of straight vacation, 3 days of extended vacation (assuming you exercised that option), 4 days of buffer, and 9 R-days. If adjustments need to be made, you get to state your preference for how the adjustment is made (e.g., remove the R-day on the 23rd, or add R-day on the 9th).
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