You are correct in that there should have been no wait on the flood policy.
The post doesn't give the expiration date of the policy, only that they sent the force place letter on Jan. 5th. If the borrower did not renew the policy within the 30 day grace period then there would be a 30 day wait period for the new policy to become effective. If the policy was renewed within the 30 day grace period then I agree there should have been no wait period.
With the Christmas and New Years holidays the policy very will could have expired 12/22 (as example) and they (the bank) did not get the notice until 1/3 and mailed the letter on 1/5. If the policy expired on 12/22 the grace period expired on 1/21. If the new policy is effective 2/26 that means the borrower did not renew the policy until 1/27, after the grace period expired.
_________________________
The opinions expressed are mine and they are not to be taken as legal advice.