Have a new card which started at midnight last night. When I start work at 8am today how do I add the manual entry for the time from the end of my last shift yesterday as it won’t be recorded on the new card? In my mind I would put the old card in, add a manual entry for the time up to midnight, then replace it with the new card and do the same from after midnight. I’m fairly sure I didn’t bother doing anything special last time I got a new card but the company I now work for is very hot on tachomaster infringements and so far (touch wood), I’ve managed to keep my record clean so would appreciate any guidance. 
That’s a good question.
I would suggest see what it asks for when you put the new card in and carry on from there.
At worse - do a print out and make a written record for the manual inputs you would have made. Do two - hand one in and carry one for 28 days.
Could always put ? in as the manual entry.
Keep the card for 28 days, no need for printouts.
Manual entry required on the new card.
It won’t accept the old card as it in layman terms locks it.
Just follow the prompts if need be do a manual entry on a strip of print out paper.
Just for future reference, & thanks for the replies. As Nick says, the old card comes up as ‘invalid’, so just ejected it. Putting in the new card came up with ‘end of duty?’ date of mid February, which is when I guess the card was made. I had a slightly older tacho which didn’t have the option of ‘?’ entries so I ended up scrolling the date through to the previous day, adding a manual entry for ‘end of duty’ matching the previous card and then did a normal start of duty manual entry for the new day. Did a printout anyway, just in case it recorded the month prior to the previous day as continual working (Need to cover ■■■ for absolutely everything with current employer) and it didn’t mention anything before the previous day so all well & good, no infringements have appeared anyway.