We need to change fiscal years so that it will be like:
2020-01-01:2021-03-31 <<<15 months

2021-04-01:2022-03-31

The client had no number series defined for NL transactions and some transactions dissappeared after importing into the DB, because (I guess) numbers overlapped.

Maybe there are some tricks to renumber transactions during the import/export?

Or should I write some export/import/maintenance to do this?