I'm wondering what you mean by "Compulsory Skating"? Do you mean figures?
Or are you wanting to just do what I might refer to as "basics" - edges, stroking, turns etc.
If you are wanting to do figures and you haven't done them in a long time or are new to figures, you can use just about any type of blade - the Pattern 99 should be fine... for a while. If you are wanting to do more advanced figures then an actual figure blade (very shallow hollow, no bottom toe picks) would be good (or you can get someone to convert a pair of regular blades (like those Pattern 99s) to a figure blade by shaving down the bottom pick and making a flatter hollow.
For basics I would say that the Pattern 99s would be fine. If they have been sharpened pretty flat you may want to get a new pair so that you will have a nice new rocker to turn on.
Welcome back to skating!