We are migrating a large site collection from SharePoint 2010 to Office 365 SharePoint Online, starting with a single site (for testing purposes).
The site collection uses InfoPath forms quite heavily. We will eventually move all these InfoPath forms to PowerApps/Flow but for now, considering the goal is to first get off SharePoint 2010 entirely, we'd like to be able to do that part at a later stage.
Is it true that InfoPath forms are not supported by the Modern Site experience and thus must use the Classic site experience? (or is this an assumption I have made?)
If I create sites in the Classic experience initially, what effort will it take to modernise them at a later stage?