Are they doing only standard RPA or also Robotic RPA? Since licensing is extra for Robotic RPA versus free RPA (attended).
So logically there isn't a license until you start looking at scenarios with connectors and cloud flow integrations and I am not sure which of those or all you are allowing people to do and also depending on what M365 plan you have, and if people are developers with developer licenses.
Are you looking at using Premium PA licenses? (with or without Robotic RPA?).
Your organization seems very large which is cool :-) but if you do that you need to segment somehow. Even at Microsoft, we had different environments for different segments (sales / F&O etc) so you might want to look into that as then you can track license charge backs by environment which is pretty straight forward.
However once you start allowing things like AI Builder or Copilot etc it becomes confusing a bit again because some things are then included for free in CP licenses.
But either way I would segment by some agreed BUs / Organizations / environments.
Would have to know more to give the best answer possible.
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Thank you!
Sincerely, Michael Gernaey