How to properly predict date using Orange 3
So you have two independent variables. iOS version and release name, which is actually a type. Both are categorical and only one has any predictive power, because iOS version you are trying to predict does not appear in your training set. Thus, effectively, you are predicting based on the release type only and only the "release" category is actually meaningful because this is what you are trying to predict.

I can hardly think of a model that would perform ok with such limited information. Anyway, regression models will always give you some answer, even if your input is unsound.

I guess the better features would be:


month
day of month
days since last release
months since last release
years since last release
days since beta
months since beta
years since beta


This type of thinking. Then just by looking at the data you would clearly see that prod releases of iOS happen always in mid Sept each year. No need for model to figure it out :) Any method would suffice, especially kNN or least squares.