You should be able to check if their license is subscription by looking at their product list on the Sage Portal.
I think the dial-home-to-check-expiration-dates was added around v2015-2016... older than that "shouldn't" be affected by the TLS license server issue unless they tried to install the old version on a new server.
I'm curious if perpetual clients on v2015-2019... will be able to do a server move (without upgrade) after October next year.
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Kevin Moyes
Technical Systems Analyst
Munjal White Consulting Co.
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