I don’t think that they would accept that course of action or defence at the roadside though and their attitudes seem to be hardening to the 28 (soon to be 56 days) day roadside production requirement. In many ways they are asking infrequent users of the digital Tacho (like the opening questioner in this exchange) to be more accomplished in using that Tacho then a full time driver.
This is made worse following the amendment to Art 6(5) of 561 which removed the phrase “since last daily / weekly rest period” - it’s now open ended and seems to open up the possibility of a goldmine of Roadside Penalty Tickets and prohibitions.