Maintenance of 5 custom joomla modules

I had a Turkish developer team to make 5 custom Jooma 3.x modules for me. Unfortunately, they are changing their business in another direction. Therefore, I seek an experience Joomla developer who can participate in knowledge transfer and help lift the code to Joomla 4 and fix issue if they occur.
Major module is a calendar booking (with DPcalendar) with some business rules and a module to filter articles in a timeframe.
I prefer Time & Material based on a initial estimate.

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