Need some guidance for MBA prep with a full time job

I have been working as a Software engineer since the past 2 years (work from home), but now I will have to shift. I have been thinking about going for an Mba since last year and will be self-prepping, since I have the basics (I did prepare last year) I am confused on the course for preparation I've been thinking to go full on with Mocks and tests for the time remaining (I'll start the prep now)

People who have been in similar situation, what mock test series did you find accomodating and flexible ? I would want to have as much flexibility in mock tests because some days I can devote 4-5 hrs, but some days it would be lesser. I've come across SIMCATs, AIMCATs and CatKing's mock series. Are they good ?