Clarification on Expiry Rules for Clay Referral Program Credits

I’m using Clay and have noticed the referral program rewards 3,000 credits for each successful referral. I couldn’t find any clear information in the documentation or FAQs about whether these referral credits have an expiry date, or if they follow the same rollover rules as regular plan credits. Could someone clarify if the referral credits expire, and if so, what the rules are regarding their validity?