Hi Joi, if the seller accepts a late-delivered option check (as in your example), we take the position that seller has then ratified buyer's right to an option period, and therefore, buyer could terminate under the option just as if buyer had paid it on time. In other words, by accepting the check late, seller has waived the right to say that buyer does not have an option period because it was late. Seller is considered to have "accepted" the check late if seller has formally receipted it or cashed or deposited it. If seller simply holds the check but does not receipt it for buyer or cash or deposit it, the issue is murkier. Dawn discusses this issue further in her video from 6-1-17, available here: https://allegiancetitle.wistia.com/medias/5xd4kx0vma
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