Bonus while on maternity leave

Hello,
We are wondering if an employee can be paid for a yearly bonus for 2021, paid out in February 2022 without it affecting their current EI benefits (maternity). The employee has commenced maternity leave in January 2022 and noted that as long as the company can confirm that the bonus relates to 2021 it shouldn’t be a problem and we would just need to reissue an ROE confirming the same.
Can you confirm if this is correct? My understanding was that since the payment of the bonus is in 2022, it would be considered 2022 income and as such, would be deducted from her EI benefits.
Thank you,
Zsofia