It is often recommended to retest any time you change your primary power measuring device, right away. This includes any change from one power meter to another. It especially applies when switching from something like the InRide (which is basically Virtual Power) to a real power meter. As much as we’d like, we can not freely assume these meters will match, because most often they do not.
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Swapping devices means you are likely to get different training that is too easy or too hard.
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Also, since you effectively change “tape measures” you can’t really say that you lost or gained watts. You did a test with one tool, did some training, switched measuring tools, did more training, and did a test. You should not compare the old and new test.
Just ignore the old info. Use the current power meter data and move forward in your training. Keep everything as consistent as possible, and you can compare data over time. Change any variable, and that becomes more tricky and in some cases (like this one) totally irrelevant.
As far as calibration, there’s no way to know. Make sure you follow the manufacture process and recommended frequency. That is the best you can do.