Early Retirement Window - Eligibility Limits

[HCE]

We have an Early Retirement Window for our pension plan going into effect.  We crafted the eligibility requirements and are comfortable that they are fine.

However, today, we discovered that four people at a key position at the company might want to participate.  There are only 4 people in this position company-wide, and having them all leave at the same time would be devastating.  Can we state in the eligibility section that, for this specific position, only two can participate, and the people with the longest service at the company have first dibs?  Thank you.