There is the option to pay for a month (fees are in USD). You can choose the cheapest plan that will accommodate the amount of records before you canceled them, and do what you need to do with your records to keep within the limit and then cancel your subscription, before the month is up. Or you can contact Airtable, but that might take about a week or so for a reply.
Unless, someone else might have a suggestion, in the Airtable Community.
What I have done with the free plan, is I split up my database into about 500 records, in each base (to accommodate future base growth) and then I just titled it, showing the range of unique numbers in that base, so I can see right away which base I need i.e. SCOTT# 1-500. I don’t know how that would work for you, but it’s one soluttion, without having to pay and you could still have as many records as you need.
Hope this helps.