I had fun last night, my old digicard expiry date is/was 16-05-2011… so i would assume that it would work ok until midnight… i started my night trunk at 1845 BST (1745 UTC All seemed ok until about 1905 when i glanced at the tacho and saw it displaying DRIVING W/O CARD… i pressed OK… that brought up the message INVALID CARD… so i pulled into the next services, tried to get a driver printout, but could only get a vehicle printout… then i ejected the old card and inserted the new one (start date 17-05-2011), same message, INVALID CARD… So my decision then was to continue my journey, have 15 mins break after 2 hrs, then do my trailer swap and have an hour break after 4hrs 15 mins driving and other duties. after all this it was 1am BST… so i once again inserted my new new card… SUCCESS… BUT there must be a problem with the old card not having been programmed correctly… is there anyone on this forum from VOSA or DVLA who could shed some light and perhaps follow it up so that other drivers dont have the same thing happen to them.■■?
It’s a well known issue-to all except you! 
44 Tonne Ton:
It’s a well known issue-to all except you!
so why havnt vosa or the dvla sorted it ■■?
Trukkertone:
44 Tonne Ton:
It’s a well known issue-to all except you!so why havnt vosa or the dvla sorted it ■■?
They have, in that little booklet you threw in the bin when your new card arrived, it tells you about the crossover and to take a printout.
It is a good job i kept a copy just for you!
DVLA is aware of an issue with driver and company cards issued before 26 August 2006. Driver cards will stop recording activity and company cards will stop locking or unlocking and downloading data 24 hours before the expiry date. Estimates are that 65,000 driver cards and 14,000 company cards will be affected. Any cards replaced since 26 August 2006 will not be affected.
The affected cards will show as invalid for this day and will be treated as malfunctioning. There is no need to notify DVLA or return the card on this occasion. Cardholders can continue to drive on this day but must keep records using the print out facility on the Vehicle Unit (VU).
When DVLA issue the renewal reminders the affected cardholders will be informed of this problem and advised of the VU printouts procedures. DVLA will also inform cardholders on where they can find additional information, including how to contact one of Vehicle and Operator Service Agency’s (VOSA) traffic examiners.
You should get on here more often! 
Why the DVLA didn’t just backdate the new cards by 1 day to solve this problem, is anyone’s best guess.
Oh, I know why not, because it would make sense… bloody DVLA!
44 Tonne Ton:
You should get on here more often!
I know I should, but i need to go out and earn a crust now and again so i can pay my taxes to support all my thousands of dependants…( dont get me going on that one… LOL ) AND the only info that came with my new card was DVLA VOSA booklet INF177B digital tachograph driver card information. NOWHERE in this booklet does it mention any problem… and DVLA booklet Tiredness can kill- advice for drivers INF159…
So , as usual, us drivers are once again left in the dark to figure it out ourselves…
Trukkertone:
So , as usual, us drivers are once again left in the dark to figure it out ourselves…
The information about the card not working on the last day was certainly sent when I renewed my card, though I think it may have been in the accompanying letter rather than a pamphlet.
Trukkertone:
44 Tonne Ton:
It’s a well known issue-to all except you!so why havnt vosa or the dvla sorted it ■■?
They did, they sorted it from the 26th of August 2006. 
Envelope with the new card, to replace my current card when it expires on 30th June 2011, in it was here when I got in from work this evening. In the envelope is a sheet of A4 paper with the card stuck to it with important points to note such as looking after the card, checking the details are correct and it’s not my card it’s the Secretary of State’s. Two leaflets also included. One, INF177B with information about the card and INF159 about Tiredness Can Kill, have they been reading my posts about the average sleep I have?
No mention of the card not working on the last day problem included, but maybe that is because my current card was issued after 26th August 2006?