Getting replacement coverage, even temporary, before you list removes this as a risk to the timeline entirely. Insurers ask why a policy was cancelled, so knowing and being able to explain the reason, whether it was a claim, an underwriting change or the home sitting vacant, speeds up getting a new quote.
A buyer's own lawyer will also ask about insurability during their due diligence, particularly on an older home, so disclosing the cancellation honestly in the property condition disclosure statement avoids the issue resurfacing after conditions are supposed to come off.
Solve the insurance question before the first showing and it stops being a timeline problem at all. Get your hand-reviewed valuation from Joel Dyck.