Read it on the day it arrives
Lithuania works in Lithuanian, so an English record needs a Lithuanian text beside it before an office there will act. That text is checked before it leaves, but the person who knows the source best is you. Names, dates of birth, the spelling of a village, a surname that changed at some point — those are details a family recognises instantly and a stranger has no way to verify.
The reason for reading it early is not doubt about the work. It is that a file already lodged with an office is far harder to pull back than one still sitting on your desk. A correction caught before submission costs a short exchange of messages. The same correction caught afterwards can cost an entire round of the process, plus whatever the wait was worth to you.
A correction and a new job are not the same thing
Some findings are plainly corrections. A transposed digit in a date, a name rendered two ways on a single page, a line skipped out of a signature block — each of those came from the Lithuanian text and is put right in the Lithuanian text. The certificate of accuracy is then signed again to match, because that page states this text corresponds to that source, and the pairing has to stay true.
Other findings look like errors and are not. If the sheet you supplied is itself wrong, or you send a different sheet halfway through, the Lithuanian now describes something new and is priced as new work at about £25 for each page. An official Lithuanian translation in Nottingham mirrors the paper it was given. It has no authority to improve that paper, and would be worth less if it did.
What a reissued certificate replaces
Once a corrected text goes out, the earlier certificate of accuracy stops being current. Set the first version aside rather than filing both, because two signed Lithuanian texts of one record, differing by a single digit, are exactly the discrepancy a careful reader is trained to spot. Only one version should exist anywhere in the bundle you hand over, and it should be the last one signed.
Where the underlying record is a civil one registered in this city, the cleanest repair is often a new source rather than a new translation. Nottingham Register Office issues a fresh certified copy of a birth, marriage or death entry from The Council House, Old Market Square, Nottingham NG1 2DT, so the original you keep at home never has to travel or be handed over at all.