I’ve been driving wagons now for 5 years. Probably had around 10 employers in that time, and the only one that has ever bothered with manual entries was Maritime.
If you are new to driving/tachograph’s, my advice is not to bother with manual entries unless instructed to do so. If you are paid based on your tacho then I understand a manual entry, otherwise until you get comfortable with using a tacho, simply don’t bother.
Tachograph (as in TNUK member) is a valuable source of knowledge on here and is the Yoda of all things digitally recorded 
I heard a rumour once that he evens lifts the toilet seat when having a ■■■■■, he’s that sort of guy! (Read his excellent tacho guide for noobs 
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