It could still be, since the error happens from not having the mod installed rather than a conflict with it.
Basically, when the mods are changed or updated, this mod is updating which recipes are available based on what technologies have been researched in the save. However, it tries to look and see if you've researched "phosphorus-processing-2" without actually checking to see if that technology exists first (or if the mod that adds it is enabled). Trying to find something that doesn't exist in this situation makes it crash with the null reference exception you got.
The fix for this, as with the other case, is to just add a check to see if the relevant mod is installed before trying to find the technology from it.
When I try searching for "phosphorus-processing-2" I mostly get MadClown results, which is why I suspect that it is the mod in question.
Interestingly, I also found the same issue with the same tech reported on a different mod (also involving Extended Angels), with the changelog suggesting it was due to MadClown's Processing: https://mods.factorio.com/mod/Better_Angels_Smelting/discussion/5d7f963f64c43b000d8f2d88