Airtable has a hard limit of 50,000 records across all tables in a base though.
Airtable-wise, I'm parroting our devs on the subject. We had perpetual/nascent plans for an Airtable migration (and did so when FindTheMakers came to life) which have been tabled for now. We believe we'll make it to sunset on Sheets, but just barely.
Is there some special meaning of "record" in their vernacular?