If I am in your position, I would quickly give certification, as the fee for Business One Certification is less compared to normal SAP Certification.
If you want to give certification, you would have forgotten most of the things if you are not working. At that point it would be more difficult for you give the certification.
Therefore, plan accordingly and appear for certification at the earliest.
Ultimately, Certification is a personal choice, but not a compulsion. However, you would be recognized by your prospective employers based on your commitment to learning and education.
All the best.
Kind Regards,
Ravi