Should I continue with filling it out for a single group or both groups? is one of the most crucial questions on any CA aspirant's mind at this point.

You can make a decision based on the following important factors: 

Check your level of preparation: If you are confident in all of your strong subjects at this point, you may want to consider assigning more time to your weaker subjects in the remaining period. You can attempt a few CA Mock Test Series to analyze this. This will allow you to better organize your strategy and provide adequate revision time.

Your judgment is your own: Making an informed decision at this point might be aided by careful review and analysis of your time. Nobody can evaluate your ideas for both groups or just one group better than you. The mock test for CA that you will attempt can help you in this.

It's the time for revision, which is really necessary. You should never consider studying until the month before your exams. You will always benefit from the written revision since you will learn whether you can answer the questions confidently, accurately, and promptly.

Avoid comparing yourself to others: Comparisons need to never be made. Never choose an approach that relies on comparisons to your past choices or those of your friends.

Going for Rank: Those who attempt both groups together are given ranks. Therefore, the rank aspirants will also determine whether to move forward with both groups, which is something we should all aspire for to manage our preparations well.

The advantages of taking both groups are:

Saves time: As the exams are held every 6 months you will have to spend another 6 months to write the second group of papers. You can save 6 months of study time if you attempt together.

Cost-effective: Along with time and additional effort you can also save money. You will have to register again, for CA inter the registration fee for one group is 11,000 whereas for both is 18,000.

Better chance at getting an exemption: As you attempt both papers you will have to write 8 exams. So, you can get exemptions if you get more than 60% for a paper. So, in the next 3 attempts, you are exempted from writing these papers if you have more than 60% marks. So, in case, you fail overall and you got more than 60% in a couple of papers then that is an advantage. So, if you appear for 8 papers, you will have more chances to get an exemption.

Disadvantage -

Preparation: Of course, the biggest challenge is getting ready for both groups at the same time. You have to be very well organized and have a very effective study plan with you. If you are pursuing other courses simultaneously, or you are under time pressure for other reasons, you may want to think of clearing one group at a time.

Attempting 8 papers at a go: All said and done you have to attempt 8 exams in a single shot. This can be mentally very stressful. You may also feel dejected when you see your friends who finished one group free in about a week's time. Imagine the number of books, revisions, mock tests for CA and topics to go through.