MacBook Pro Battery Drain
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Unfortunately I upgraded the computer from High Sierra to Mojave at the same time as replacing it's internal storage from 256 Gbyte to 1Tbyte so I do not know for certain which is to blame (or neither and I have now only become aware of a gradual deterioration).
I suspect the SSD card. I could swap the card back as an experiment but as there is no way I am going to stay with the 256GBytes card my only reason would be to advise others of a consequence of upgrading using the OWC (Other World Computing) card.
Any ideas?