Hi Erik
Interesting to go deeper on operational processes but your question is quite large, I think you can find more information on ITIL sites rather than TMF site for that.
I suggest as a first input to have a look on this link:
https://www.thinkhdi.com/~/media/HDIConf/Files/Copy%20of%20Handouts/Session202.pdfFor your information my company (telecom services) reach globally an average under 30mn for MTTR.
Kind Regards
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François ROUL
Orange
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