We had a project last year where I had to merge a legacy PR company code into an existing Premium system. Basically the concept was to copy the MAS_### folder in place and convert, so I think you could do a test migration with company system files, do all the conversions (as proof of concept / advance testing), then re-copy each company folder / reconvert as you want to move them over. System files (paperless logs...) will have to be dealt with manually, no new UDF's in the transition, and try to avoid new users (user key issues).
(I'm not a Payroll Guru... this was the only time I've ever touched PR in any capacity).
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Kevin Moyes
Technical Systems Analyst
Munjal White Consulting Co.
Toronto ON
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