Hello Kshama 

actually the material from allen institutes maybe from any year it be is best for preparing as it contains a lot of good questions and it is designed in a way a student can easily study from it,you cannot completely rely on it as there might be a lot of question patterns from this 2 yrs but for basics and more good questions you can rely on them.

Take them as an extra study material.

hello

kshama chakraborty 

The allen study material of 2016 is not sufficent for the JEE mains 2020 why i am telling negative about that becasue i am not blaming the allen study material it is the one of the best material according to my knowledage but u should more concerntation on the NCRT text book it is the main source 

so please study well and also keep rocking 

thank u