If the subscription stops, you can choose to:
1) If you like Flexi, renew the subscription and open the FS files
2) If you like Flexi, purchase a perpetual license and open the FS files
3) If you do not like Flexi and do not need any of the Flexi Files (FS) you created, purchase a different design solution such as Illustrator or a free version of Inkscape (Start Over)
4) If you do not like Flexi, save your files as FS, EPS and/or PDF as you go, cancel your subscription for whatever reason, purchase a different design solution such as Illustrator or obtain a free version of Inkscape and import your EPS or PDF files to avoid starting completely over for every client you have do work for.
If you intend to stop your Flexi subscription in the future, want to continue your design/sign business and want the ability to import the files for later use, you better export them into a more open format such as EPS, PDF, Etc. or be willing and able to recreate anything you can not access.
There are all kinds of reasons for and against a subscription model of any software. Do I like the subscription model? Not really but it is an option for all to choose. Is it a viable option? Yes but not for all.
If you have been successfully using out of date software(s) and are happy with the features/workflow you have access to, then you found a good solution for you and your business.
Again, I hope this conversation helps someone in some way