Wording of Sunset clause in reinsurance contract on risk attaching basis:

“It is a condition precedent to the Reinsurers’ liability hereunder that:
Any accident and/or occurrence covered hereunder arising from a policy issued on a losses occurring basis, shall be notified with full particulars by the Reinsured to the Reinsurers within 48 months from the expiration or termination date of this Contract.”

Let’s understand the impact by an example:

Reinsurance treaty: 1/1/24 to 31/12/24 covering all risk attaching during this period.
Sunset clause: 4 years:
Notification to reinsurers with full details before 31/12/28
Occurrence based policy issued by primary insurer from 1/12/24 to 30/11/25
Loss occurred on 1/11/25
Claim was notified to primary insurer on or before 31/12/28 and primary insurer immediately notified to reinsurer-reinsurance treaty covers.

However, Claim notified to primary insurer on 1/11/29. Primary insurer liable (assuming they do not have a sunset clause in their policy matching this condition), but reinsurer not liable.

Renewal of reinsurance treaty:1/1/25 to 31/12/25
Sunset clause: 4 years:
Notification to reinsurers with full details before 31/12/29.
Notification of above-mentioned claim within this reinsurance contract sunset clause but this treaty will not pay since risk did not attach during this reinsurance contract.

Can we solve this issue by having a “SUNRISE CLAUSE” in every treaty renewal? If yes, what should be the wording? And what period should it additionally cover?

Or is it better to have the reinsurance contract on loss occurring during basis? Or on “Claims made and Losses Discovered Basis”?

Let’s all think about it-are we studying the primary coverage in detail before planning the reinsurance coverage? or are we just renewing the same wording year after year?