After a conversion strategy is applied, all levels returned by IConversionStrategy.getLevelsToBeRemoved are removed from the language levels of the feature model, but the levels from IConversionStrategy.getTargetLevelsOfConversion are not added. As long as conversions only go from major -> next lower major oder minor -> corresponding major, this should not be a problem, but if conversions are performed between arbitrary levels this should be considered.
After a conversion strategy is applied, all levels returned by IConversionStrategy.getLevelsToBeRemoved are removed from the language levels of the feature model, but the levels from IConversionStrategy.getTargetLevelsOfConversion are not added. As long as conversions only go from major -> next lower major oder minor -> corresponding major, this should not be a problem, but if conversions are performed between arbitrary levels this should be considered.